yashsingh1/xdaforums huggingface dataset:
[Galaxy Tab S2 Android Development] Flax_:
@ripee any chance the faint microphone will get fixed on T810?

more or less the only real issue left with this great rom.

Else is there maybe a workaround?
[Galaxy Tab S2 Android Development] rabbitkiller:
About the WiFi connectivity I remove the dhcp ( and the ipv6) and it's OK now.

I have got battery drain some time too.
[Galaxy Tab S2 Android Development] phaleg:
Hi, I am a normal user that decided to share back his experience, hoping to help other people moving from stock to custom ROM.

Device = T815 running stock Nougat (no Root), also known as GTS210ltexx

STEPS

(!) Start with full battery and get the best USB cable you have. This process requires external SD (or aternatively USB OTG)

Click on build name of your ROM until it says you are a developer.

Back once and click on developers' option menu to enable USB debugging and OEM unlock (if OEM unlock is not present, skip it)

Download and install the latest Samsung USB drivers from a trustable source

Download the latest TWRP custom recovery file for your model and put it to external SD and also to PC desktop

Download the proper version of the ROM you want, Gapps (if needed), Magisk and DFE (last file is to prevent encryption), and put it to external SD

Connect the tablet at least once (with device on, normally) and wait that Windows has it fully recognised and working

Shut down the tablet for at least 5 seconds

Install the latest version of Odin (link in wikipedia) and execute it as admin

Turn on the tablet in download mode (Volume Down + Home + Power), then volume Up when you get the warning to continue

Plug it with cable and check that Odin states "ADDED" in a small blue square on the left

Load in Odin the *.tar file of your recovery (from PC) in the second field, in the tab options keep the tick to Reset Timer, (untick auto reboot)

Click Start and wait until the end, it should state "PASSED" on PC. If it fails, repeat the process once more.

Once it is done, please, DO NOT reboot the unit, it will overwrite the recovery, but do the following.

Plug the tablet to charging in the same mode it was before. Wait that shows the charging animation. Force turn it off with Volume down + Power until fully Off

Turn it on again after 10 seconds, with Volume Up + Power to load TWRP (recovery). Swipe to allow system modification if prompted.

Now you are in TWRP !

Backup the default selection to External SD

(!) Be sure the recovery reads your external SD with all the files you need

Start with wipes: system and both caches. Then format DATA (confirm with yes, if requested)

Flash in this order: ROM, Gapps (if needed), DFE. Flash Magisk after first boot to stay safer.

Reboot system and WAIT, first boot takes longer, do not touch it for a while also after loading, give it 5 mins

My result is that I have Lineage OS running on the Tab S2 without any knox alert

Do not use or store fingerprint for a smoother experience.
[Galaxy Tab S2 Android Development] amin115h:
Hi there i came across problem it suddenly goes to twarp middle working and finger print scanner dose not work can anyone help me i appreciate it model 2015 t815 lte
[Galaxy Tab S2 Android Development] lpedia:
Do you mean it suddenly rebooted into TWRP and is not responding?

If that is what you meant: try forcing a reboot by holding Volume Down and Power for about 10 seconds (with device not connected to PC or charger).
[Galaxy Tab S2 Android Development] KingN96:
Hum....after few days without sudden reboots, they returned last night, so turning off fingerprint sensor doesn't mitigate the issue. could be something related to the battery optimization? It's strange that these reboots coming always (at least to me) during a long standby period (if you don't use the tab for some hours with offline mode activated)...
[Galaxy Tab S2 Android Development] lpedia:
I've seen it happen while I'm actually using the device as well. Sometimes it reboots cleanly, but more often it seems to get stuck on boot animation. If the latter, I've found, it usually hasn't actually rebooted. It will be running BootAnimation after logcat reported "The system died", then trying but failing to restart, and repeating that sequence. adb can talk to it, but adb reboot [system | recovery] doesn't do anything: it has to be manually reset.
[Galaxy Tab S2 Android Development] dombo1970:
Using T810 with 17.1 (01012021), the device switches on immediately as soon as it is charged and boots into Recovery.
[Galaxy Tab S2 Android Development] phaleg:
Howdy!

What to do when it randomly reboots to TWRP?
[Galaxy Tab S2 Android Development] bbortnick:
Live with it or install an older build. i am running 20201227 and I find it quite stable (only problem for me is fingerprints, and I don't need fingerprints.)
[Galaxy Tab S2 Android Development] kabelgleichung:
Disabling DHCP did not work for me. How did you disable ipv6 in Android for WiFi? Or did you disable it on your access point?
[Galaxy Tab S2 Android Development] phaleg:
The random reboots to TWRP and / or that found the tablet with zero battery despite I remember that I turn it off with still charge on it?
[Galaxy Tab S2 Android Development] lbanias:
SM-T715 : installed lineage-17.1-20210116-UNOFFICIAL-gts28ltexx and open_gapps-arm-10.0-tvstock-20210116 and reboots only to TWRP, ask me read-only or not. Chosen read-only or allow modifications but still reboots into TWRP after showing 5 mins lineage logo. Also tried rebooting with power+volume down. Ideas?
[Galaxy Tab S2 Android Development] phaleg:
My humble opinion is that the TVstock package is not for our tablet...
[Galaxy Tab S2 Android Development] Flax_:
T810 using since 01.01.

0 random reboots.

Did you guys try a clean flash?

I dont use fingerprints!

Only things i noticed:

- mic is still faint

- some real rare wifi drops

Besides this a perfect daily driver

*edit

Just saw that there 2 new versions out o_O

Is there a change log to them?
[Galaxy Tab S2 Android Development] lpedia:
My experience so far:

T710 using 20210101, clean flash.

Battery life is usually really good (unless it drops to BootAnimation while unattended).

Fingerprint unlock doesn't work - haven't tried opening apps with fingerprint. If there are any FPs registered, going into Settings > Fingerprint hangs Settings app. Wiped fp and didn't try again.

Quite often drops into BootAnimation and has to be forcibly reset. Sometimes days between incidents, yesterday twice in one day, once so far today. Can happen while I'm using it, or while it's locked / asleep.

Often doesn't automatically reconnect wifi on unlock / wake from sleep, but turning wifi off + on forces connection. Once connected, wifi usually stays on while it's in use.

Haven't tried mic

Installing / not installing Gapps package makes no difference to this behaviour.

It's still usable for my purposes (which is mainly as an ebook reader).
[Galaxy Tab S2 Android Development] bbortnick:
My T710 on the older build is quite reliable. Your results may vary.
[Galaxy Tab S2 Android Development] MrBlubke:
what's the change log for the build of 20210116? anyone know (t810 here)
[Galaxy Tab S2 Android Development] dombo1970:
Actually the wifi problems and power-off problems are gone, since I flashed this version on my T810.
[Galaxy Tab S2 Android Development] MrBlubke:
Ah, looking forward to that, had it installed, but didn't experience any difference right after installing so was wondering, this would be great then! I'll report back my findings
[Galaxy Tab S2 Android Development] phaleg:
I had the issue with build Jan1, now with newer is going better
[Galaxy Tab S2 Android Development] dombo1970:
This morning it was uncharged again, so: Sorry, this bug is not fixed yet. Strange, wasn't happening the last days.
[Galaxy Tab S2 Android Development] Flax_:
clean flash? what gapps did u use? Model T710? oder 810?
[Galaxy Tab S2 Android Development] Surfer_II:
Same here on T810 with 01/16 17.1 build. Besides unstable WIFI, tablet also has random reboot/boot animation loop issue and huge battery drain to zero % within few hours related to boot animation loop and tablet gets warm.

No relation to fingerprint (is disabled on my tablet).

Charging speed is quite slow - only ca. 15% per hour.

On T815 such bugs did not occur so far. Runs quite stable on 01/16 17.1 build besides the charging speed which is also slow.
[Galaxy Tab S2 Android Development] Flax_:
Thats strange. i have T810 with 01/01 build and nano gaps and 0 issues since 01.01. except 1 wifi dro and faint mic. No reboot, no bat. drain.

Haven´t tried 01/16 yet cause i dont know the changelog....
[Galaxy Tab S2 Android Development] MrBlubke:
I'm going to check for battery drain tonight, but with a dirty install over 01/01 version the wifi issue is still there on my t810...

so still curious about the changelog....
[Galaxy Tab S2 Android Development] MrBlubke:
battery drain is cefnitly there.. so is wiifi issue issue
[Galaxy Tab S2 Android Development] lpedia:
Ditto with dirty-flashed T710. This morning I found it had hung overnight partway through a boot animation, and wasn't responding to adb. With the earlier version the boot animation would be active (but very dim) and adb could still see the device and open a shell.

I have also had several sudden reboots since installing this version ~two days ago. The wifi issue doesn't seem to have changed.

As long as it doesn't drop into boot animation loop, the battery doesn't discharge at all while it's asleep.

I'm going to clean-flash and see if that makes any difference.
[Galaxy Tab S2 Android Development] lpedia:
Hmm ... the wifi issue isn't uncommon with other environments. I found a reference to one newer Galaxy tab type that had exactly this problem after update to (stock) Android 10.

It's also very similar to a commonly reported issue with Qualcomm wifi in laptops [Edit: running Windows 10], which I've experienced with my Dell Inspiron: although configured to automatically connect to a particular network, it doesn't always do so on reboot or wake from sleep / hibernation. Suggested fixes for that problem, and the only one that had any effect on my machine, include turning off the wifi interface's 'Allow the system to turn this device off to save power' setting.

This might also apply to Android. I've read that the Android battery saver can affect automatic reconnection because the wireless interface doesn't get power soon enough after wake or startup (and doesn't try again automatically once it does turn on). This could explain why it tends to stay on once it connects.

I don't know how to test that - I don't see anything obvious in Settings. Automatic battery saving is not enabled.
[Galaxy Tab S2 Android Development] MrBlubke:
If that would be the case, it might just be a matter if adding a delayed start somehow to the interface after waking up from sleep... not sure if that is possible, but would sound like the solution then... after that it would just be a matter of fine-tuning the delay to not be longer than required to be thrust worthy...
[Galaxy Tab S2 Android Development] Wking1:
Seems like a good clue worth more investigation.

While the Jan-16-2021 seems to have slightly more stable WiFi it still is not resolved. I have a more unstable connection the farther away from the router I am. Signal strength indicators are lower than on my phone which shows about 4 of 5 bars in another room and my t715 shows between 1 and 3 bars in the same spot. Drops occur less to not at all if I'm in the same room as the router.

The Jan-16 build has also has had more full battery drains than Jan 1 build - at least for me.
[Galaxy Tab S2 Android Development] jpq:
Same here on my T710 Clean Flash
[Galaxy Tab S2 Android Development] lpedia:
Yes, a simple enough concept, but not so simple with Android (compared to Win10 and Linux, which both can have this problem, I found). I went looking for a task-scheduling app that could be configured to trigger on specified system events and toggle wifi off-on automatically. Tasker could do it, but seems more powerful than necessary. MacroDroid seemed simpler , so I installed that and created a macro that triggers on booting and screen unlock. It checks wifi connectivity, toggling off-on and connecting if necessary. On limited testing, it appears to work. I had to install a 'helper' app as well (explained in the app), to allow the macro to check wifi status and connect to or disconnect from a network.

Not exactly solving the problem, but it does work around it. Configuring a delay into wifi startup would be a more elegant solution. ;)
[Galaxy Tab S2 Android Development] MrBlubke:
well the delay in the wifi startup is exactly what I was talking about, just like the "delayed start" for services on Windows
[Galaxy Tab S2 Android Development] lpedia:
In effect, yes. :) But it's not a long-term solution. It'd be nice if it could be fixed at system level.
[Galaxy Tab S2 Android Development] Flax_:
Is it even verified that this delay works on these devices?

And BTW please only report bugs if you followed the rules on page 1 like clean flash etc.
[Galaxy Tab S2 Android Development] lbanias:
Thank you! My mistake...I installed the nano version and now it is ok.
[Galaxy Tab S2 Android Development] lbanias:
I installed the right twrp and Lineage OS for my T715 gts28ltexx , but the Magisk 18 is giving me the "cannot mount vendor". I read about the treble version of TWRP but I used the latest TWRP for T715 and I don't know where to find a treble version. Also , I don't know if my bootloader is unlocked since I never saw the OEM unlock option in developer settings. I need Magisk for netflix and some bills pay apps.
[Galaxy Tab S2 Android Development] lpedia:
No, it hasn't been verified AFAIK. Delaying wifi activation at startup and wakeup might help, but I personally don't know how to test that in Android. The delay would have to be inserted in the startup / wakeup sequence.

Note: if you trawl back through the thread, you'll see that people who've clean-flashed have reported this bug in all builds of 17.1 so far.

If there were release notes for each build, we'd have a better idea what to focus and report on.

Similar-sounding wifi issues in both Win10 and Linux appear to be due a race condition: the wifi hardware doesn't always get enough power at the right time to be able to connect while the system is starting up or waking up. In those OSs this can be fixed by disabling wifi power management (brute force option available to the end user) or updating to a wifi driver that cooperates better with power management (if the wifi hardware manufacturer obligingly provides an update).
[Galaxy Tab S2 Android Development] lpedia:
This device doesn't have the OEM unlock option, and doesn't need it, so that isn't a problem. If you have the latest TWRP (3.5.0_9), TWRP also shouldn't be the problem. Treble support shouldn't be an issue either. You can check a device's Treble status by running this command in an adb shell or Termux or other terminal window: getprop ro.treble.enabled - but Treble implementation began in 2017 and only on new devices with Android 8, and our T71* devices are earlier than that.

However, Magisk 18 might not have been compatible with LOS 17.1, so that could be your problem. The installation procedure might also have changed since that version. The current version is 21. The latest installation instructions are at https://topjohnwu.github.io/Magisk/install.html. Version release notes are at https://topjohnwu.github.io/Magisk/changes.html - shows support for Q (Android 10, LOS 17) being added in v19.

Hope that helps. :)
[Galaxy Tab S2 Android Development] lbanias:
Thanks, as a newbie I just read about others installing Magisk 18 to SM-T715 and never thought to search ofr updated Magisk. Now I have Magisk 21.4 installed and google safetynet tricked. I still have the wi-fi sleep/no wake problem, even without battery saver on, but I don't mind reconnecting manually from time to time. Most annoying is the zoom-in problem on video sites.

But having android 10 on a 2015 tablet is wonderful. Thanks for the good work!
[Galaxy Tab S2 Android Development] mister_ritter:
Greetings. I installed Lineage 17.1 yesterday on a TAB S2 8.0 (LTE). After completing the installation, I noticed that SE.LINUX is disabled or has the status permissive.

-Is this problematic from a security point of view? (Root is not important for me)

-Is it possible to "fix" the permissions control afterwards with other apps?

-Is there a ROM with "SE.LINUX=enforcing"?
[Galaxy Tab S2 Android Development] lbanias:
Does any Samsung Galaxy tab S2 get speedtest.net download more than 150 Mbps on AC 5ghz? After flashing android 10 still the same results as stock android 7. The main difference is that in android 10 sometimes I see 250 Mbps in upload, but never in download! Wifiman app is reporting connection of 300+ Mbps, which I have reached with other android devices( Samsung tab S4 and Huawei P20 pro) . It's like S2 tab has defective amtennas or bad drivers.
[Galaxy Tab S2 Android Development] lpedia:
Firstly, upload/download speed to/from the Internet can be quite variable. In particular, download speed can often be less than upload simply because the ISP's download stream is usually getting a lot more traffic than upload.

Secondly, for comparison, my T710 with LOS 17.1 can only manage ~150Mbps download from a server on my home network, although the wifi link speed is nominally 866 Mbps. A Dell Windows 10 laptop and a Google Pixel 3 with stock Android 11 both get ~400Mbs download speed via 5GHz wifi from the same server.

So I think the S2's wifi hardware+firmware is just relatively slow. I doubt there's a defect as such - it's just that not all 5GHz interfaces are capable of the theoretical maximum transfer rates. Their performance in practice depends on the design and implementation of the wifi hardware as well as how efficient the associated firmware and drivers are.
[Galaxy Tab S2 Android Development] lbanias:
That was the thing I was afraid...poor 5Ghz implementation. I liked this tablet so much that I have bought 3 so far, 1 as new, 2x as used, but I flashed only one with Lineage android 10. None of them ever reached 300+ at direct view 2 meters away from a TP-Link C9 router and an Asus RT-AC66U , where 2 phones and laptop reach easily 300-400 , and 200+ at 1 wall away. It's like the connect with N , not AC and have only one antenna. I put the router to wireless AC only and S2 tabs are connected, but I still get only 60-80 Mbps. Usually with other devices (wired or wireless) I have more download speed than upload from a stable 500 Mbps optical fiber connection. S2 tab is living on his own world... Lucky me , I am not a tablet gamer , so the speed nt really important.
[Galaxy Tab S2 Android Development] lpedia:
I'm no expert, but this is my understanding:

Security: For strongest Android security, SELinux should be enforcing. Security-sensitive apps such as banking could refuse to install/run if it's not.

Changing the setting: To be able to change SELinux with an app, you will need root. There are apps (and a Magisk module) that can change the SELinux setting temporarily (just until next boot). Although rooting the device will also break security-sensitive apps, Magisk can 'hide' itself from some such apps - see How to use Magisk.

ROMs with SELinux enforcing: LineageOS official releases are required to have SELinux enforcing, so the official LOS 16.0 release for gts28vewifi should. However, that's the only variant of the Tab S2 8.0 with an official 16.0, and there are no official 17.1 builds. If your device isn't a gts28vewifi, you could perhaps try the 16.0 version from the download link on page 1 of this thread (but I don't know if it's enforcing or not). The Google Drive folders contain the latest 16.0 and 17.1 builds.
[Galaxy Tab S2 Android Development] 2stardiver:
I keep my tab (t815) allways on even night, now after many nights when I wake on screen there is that boot logo running. Nothing happens from power button, and pressing volume down and power it shuts down. It have drained battery to zero.

Also that wifi disconnection bug is on every day many times.

Is there way to get back to original firmware?
[Galaxy Tab S2 Android Development] metterschling:
You might try going back to the LOS 16 variant (clean flash of course). I'm running the January build on t715 without major issues.
[Galaxy Tab S2 Android Development] 2stardiver:
Thanks, I will test that later. I noticed that there is newer 17 and just flashed that. I had 11/2020 version installed..
[Galaxy Tab S2 Android Development] GerdS:
Hi, I have a T810 running on stock ROM until I did a clean install of lineage-17.1-20210116-UNOFFICIAL-gts210wifi and open_gapps-arm-10.0-micro-20210128 yesterday.

My experience up to now:

- Fingerprint unlocking on start screen did only work once, while unlocking within apps such as Keepass2 works well

- Sometimes I get freezes which can be fixed by temporarily switching the tablet off

- Randomly the 5.8ghz Wifi does disconnect. One way for fixing that is enabling and then disabling flight mode

- My Fritzbox router has setup both a 2.4 and 5.8ghz net, as well as a 2.4ghz guest net. But the tablet sees only the 2.4ghz guest net and the 5.8ghz net, but not the normal 2.4ghz network, even if I will try to add it manually

- SELinux is deactivated

- Google Assistant complains about a network connection error when trying to set it up

- The Netflix app cannot be installed

- The biggest problem is the fail in setting up an email account

GMail is working as should with my Google account, but my other accounts (e.g. GMX) are failing indepenently of mail app used. Although all account data are entered correctly I am getting authentificaion errors, both from my k9 app or the standard email app.

Any ideas about that?
[Galaxy Tab S2 Android Development] lpedia:
About the email issue: I can't suggest a cure, but I can confirm that my T710 with this build does NOT have any problems with email. I can access Google and non-Google accounts with GMail and other mail apps.

Did you set everything up manually or did you transfer settings and apps from the earlier version (eg, from a Google backup or using a third party tool)?
[Galaxy Tab S2 Android Development] GerdS:
I tried both. k9 supports exporting and importing of settings, so I did a backup before flashing and a restore later. As login to the IMAP server didn't work, I deleted kl9 data and tried from scratch. I also tried to enter the access data within settings/accounts, both without success.

I didn't use any global backup and restore tool or service.
[Galaxy Tab S2 Android Development] KingN96:
Maybe I found a workaround to avoid boot animation loop during the standby, I've made a tasker profile that turns on the screen (just few seconds) every 2 hours and at the moment no reboots in 4 days.

I would like to report another thing that doesn't work, is the option to lock screen after x minutes. Unfortunately, also if you set 5 minutes, system locks the screen immediately after screen off.
[Galaxy Tab S2 Android Development] GerdS:
I had a complete battery discharge this night, although the tablet was set to flight mode over night. Will now downgrade to LineagePS 16 in hope this will perform better.
[Galaxy Tab S2 Android Development] Flax_:
Fingerprint is a known issue. I suggest to deactivate it compleetly by removing saved prints.

This also could fix random reboots, as i see in reports.

As of google assistant i did manually installed latest google app via apk mirror (please select your propper device).

After this every google app worked well, maybe email 2.

For wifi - i have 5ghz, 2.4 and 2.4 guest as well.

All with different ssid (name). And they work well.

But i only saved and keep connected to standard 2.4 ghz network due better range and stability then 5ghz and the fact that the speed difference does not matter for my ussage.

I further more belive that T810s hardware is not even capable of max using 5ghz speeds.

So i stick with stable 2.4 ghz

These 3 steps you can try. Hope it helps

*edit im still on 17.1 from 01.01.21