[Samsung Galaxy S 5 Unified Development] curiousrom:
S5 G900V Network, Modem & Bluetooth Problems

"Network signal drops saying No SIM or No roaming at random and phone freezes before doing so and goes to the lock screen." - I have been following this thread since October 2018 & AFAIK nobody ever reported problems like that while running in System & with a valid network connection.

Capture a logcat if it does that & look for errors.

"ROM: 8.0.1 AOSP Extended (based on LOS 15.1)" - Do a full TWRP backup + an internal sdcard backup so you may return quickly to you current setup & try a S5 super clean install & if the problem persist then report in this thread.

What is your network provider & how old is your SIM? Did you double check your APN settings?

"The bluetooth issue..." - Yes some users report Bluetooth drops on some S5's while using some Bluetooth devices. I see some work being done in the LineageOS Gerrit, some for specific devices that may make their way to the klte & some that applies to all 16.0 devices:

https://review.lineageos.org/q/branch:lineage-16.0+bluetooth

https://review.lineageos.org/q/branch:lineage-16.0+bt

"EFS partition from last 6.0.1 stock rom" - That's the one to use in case of a No network or No SIM issue after flashing LineageOS & booting to System. But if everything works fine after that & rebooting a few times a new EFS Partition backup is recommended as the primary EFS restoring option.

"Firmware: QL1" - How did you update to that modem? If you look at the haggertk's G900V package linked in S5 Odin Flashable Modem & Bootloader it includes much more firmwares than just the modem.

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Yes as reported in this thread: "the g900v is the device with the most issues".

I attached an S5 aboot to this post. This is the bootloader in the S5 that varies depending on the variant. That loads a ton of stuff before the OS kernel including modem, & other radios, etc. Unzip & open the aboot.mbn with WordPad, Notepad++ or similar & search it with modem or EFS.

Now because the unlocked G900V hacked aboot cannot be updated as to not lock the G900V again it may be old, not matched to an updated modem like in the other modem/bootloader combo packages in the linked post and that may explain the extra problems specific to the G900V.

MVNO network providers compound the problems.

Mobile Virtual Network Operator (MVNO) which is marketing speak for a reseller of network services. It's not a real network provider & sometimes they switch which real network provider they are using depending on the nearest cellular tower.

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The proprietary Samsung blobs for the radios cannot be updated passed the last ones included in the last stock Samsung ROM for each specific devices. Unless you have an army of paid engineers that can try to reverse-engineer them.

Samsung never published the codes for those.

"...these problems among others affect other devices..." - I don't have any network problems on my Galaxy S5 G900M LineageOS 16.0 klte build 2019-11-03 + Open GApps Pico + LineageOS AddonSU with the most recent modem/bootloader combo package in the linked post.

I guess it depends on which Bluetooth device too but using a cheap headset for 3 hours making calls & listening to music the Bluetooth connection was dropped once. Looking in logcat it happened when VLC was scanning media.

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