yashsingh1/xdaforums huggingface dataset:
[MTCB Hardware Development] m00n61:
I have a temporary solution until I figure out the actual cabling: Simply disconnected the front mic (it's connected to the top right of the front panel as you look from the back, just unsoldered the red wire, and connected the rear mic jack.

The bad thing is that the mic is still connected through the long original wiring.

The good thing is that the external mic can be placed much closer to you so the quality of the call improves.

I have attached a pic.

Later edit:

Here are my thoughts after all the testing:

These late 2015 units have a major improvement over previous ones - the internal mic is no longer connected directly to the BT board but there is some pre-amplifier stage and the (much higher level) resulting audio signal is sent to the BT board. Only external mic is still directly connected to the same place as before. That means that cutting the pin has no influence, you will simply cut the connection to the original external mic jack and replace that with your own.

Replacing the internal mic with a better quality, external mic is way simpler and gives pretty good results. On my GA2114 simply using the provided external mic connected as shown in the picture has improved call quality.

I now need to find a 2.5/3.5 jack adapter or cable, I have a couple good quality Parrot and Pioneer BT external microphones from older units but all these have the 2.5 jack.
[MTCB Hardware Development] mixmaster57:
Hello and thank you for the quick answer.

I asked eonon for my problem and eonon sent me a new firmware. I did an update and the problem still here.

The custumer support told me that a swap of my unit is necessary (i bought my unit 2 month ago)

In your opinion, do you think that the new unit has the problem ? Or i should do like you, mean put an external instead of the built-in mic ?
[MTCB Hardware Development] m00n61:
I think you should take the replacement they offered. There is always time later for hardware hacks :)

The problem with Eonon is they are resellers with little to no knowledge of what they are selling, especially on the software side. If you find the new unit has the same issue or just fell like trying an external microphone you can still do it. Don't forget that usually hardware hacks mean voiding the guarantee, something you should be comfortable with.
[MTCB Hardware Development] 400Fishman:
Hi,

I have a Joying (rk3188, 1024*600) Head Unit, model: JY-VQ125. I noticed than anytime I was using the hands free I would get a horible buzing noise in the background (with external mic connected or disconned, the head unit in the car or out). I was about to attempt this hardware mod but beforehand I wanted to see if changing any of the factory setting could make a differance, I simply changed the blutooth device from its default WQ_BC6 to WQ_BC6b in the Factory Setting, rebooted and now I have no more buzing noise and the sound quality is good (BT audio is also set to 0 in factory settings).

My Firmware is MTCB-JY-V2.73 with latest Malaysk ROM installed in case that matters.
[MTCB Hardware Development] dgcruzing:
wow .. can it be that easy?

got to try this and report back

I am on the same specs as you..

Edit: confirmed.. Just went for a drive and seems to be working fine..

Using stock external mic that came with unit and same settings as above..

Both callers report that they can hear me as clear as day with no hiss or back ground noise..

Sooooo good.. As was dreading opening this box up and doing the mod...
[MTCB Hardware Development] halloj:
Tested on two KLD units, both modified with sound-mod and BT-mod. There's no sound at all in the speakers during the call. Back to standard, all work fine.
[MTCB Hardware Development] HenrikH29:
Just tested it on my Joying (rk3188, 1024*600) Head Unit, Ford Mondeo model and can confirm that it Works:D

I have standard ROM (no hack) and the latest firmware ver. 2.73

Noise is gone and the sound is much better. Stange that Joying themselves hasnt suggested that as a possible solution to bad BT sound. And it must have been wrongly set from the factory.

Thanks for finding the fix "400Fishman".
[MTCB Hardware Development] Piaband:
I have the same unit as you. Joying, 1024x600 RK3188. I am also running Malaysk ROM.

I tried your recommendation. I can report that my wife says my voice sounds much better on the other end of the line. She said it is much clearer with less background noise. However, my incoming voice quality has suffered greatly. Her voice now sounds very metallic, like she is talking into a tin can. This is through my stereo, but it was much better on the WQ_BC6 setting.

I have done the external mic mod. I dont think this would make a difference on the incoming voice quality. But it still made the outgoing voice quality better.

Anyone else have this problem? If so, does anyone know how to edit the bluetooth profile? Maybe we can use the incoming settings from WQ_BC6 and the outgoing settings from WQ_BC6B.

Thanks.
[MTCB Hardware Development] 400Fishman:
Not sure if it will help much but maybe try changing some EQ settings to see if it makes a difference, I think the eq setting get applied to all the audio streams, I tend to use just flat EQ.
[MTCB Hardware Development] RabbidHampster:
I gave this a try today and it seems to have stopped the echo that people were hearing. As you said, it helped with the sound quality for the other end but has made the calls sound worse for me. I will live with it like this as I dont particularly mind but hopefully someone can come up with a more polished solution.
[MTCB Hardware Development] dgcruzing:
So far not get any problems on incoming voice on mine..

Seems to be clear for me..been using it all day driving.

I have sound speed controls off.. And have pretty much stock standard settings going on for EQ

There was a mic apk kicking round from the big thread might even pay to play with this now and see if sound can be tweaked even more..

Overall very happy with this fix..
[MTCB Hardware Development] Piaband:
I use the rock EQ. the standard EQ sounds awful for music. I'll try it though

If you remember where to find that Mic apk, please post a link. I can't find it. Been searching for good 15 min. Thanks
[MTCB Hardware Development] dgcruzing:
Should be able to find it in play store..

I haven't played with it myself but was suggested way back in the original thread..

Let us know how you go..

I will load it in over next few days and see too
[MTCB Hardware Development] HenrikH29:
I also had the sound at the other end much better and worse at my end. The sound was much louder at my end and now i have to turn up the volume (more than listing to music).

So as others wrote at combination with the incoming settings from WQ_BC6 and the outgoing settings from WQ_BC6B would be nice.

I use standard ROM, newest 2.73 firmware. BT audio in Factory Settings is set to 10 (dont thinks the setting has to do with telephone but playing music through BT instead). What do others set to BT Audio leven to ?
[MTCB Hardware Development] dc5daft:
What a great find, thanks :)

There were quite a lot of options in my drop down menu, one of which being something like Parrot_XXXX. I have a parrot mic connected to mine so I wonder if it has recognized that which I'm not sure how it would know that from just a mic input? Seems like too much of a coincidence its there anyway so I'll try it out and see how it is.
[MTCB Hardware Development] HenrikH29:
If you mean the BT drop down menu in Factory Settings it has nothing to do with the mic. It's the driver for the BT board installed in the HU - not the mic. And the installed BT board is not a Parrot board.
[MTCB Hardware Development] dc5daft:
Yeh I realised that last night when my bluetooth wouldn't connect with it selected and I googled the model number and realised it was a board not a mic :P

Changed it to the value recommended and all working good :)
[MTCB Hardware Development] gb37270:
I tried. unfortunately my phone is disconnected at each call ...

For the hardware mod : to summarize , I just had to cut the pin 4 and plug ( in the back ) my microphone on pin 4 (+) and 5 (gnd) ?:confused:
[MTCB Hardware Development] gb37270:
same for me , we have to change the hardware:crying:
[MTCB Hardware Development] rhacy:
Excellent find and post 400Fishman. Thank you.

To clarify a little, switching to WQ_BC6b improved out going BT call audio quality on my Joying (JY-UQ124 - rk3188 - 1024x600) Head Unit enough that the hardware mic mod is no longer needed. On a related note, I did set BT audio to 0 in the Factory Settings and did not notice any difference when setting it to 0 or 14. Go figure... Also, I doubt it makes any difference but my JY is running MCU-JY-2.59 darkleo, an older Malaysk ROM from early September 2015, and a higher quality external mic. That said, both the custom ROM and MCU have been rock solid for about five months now. Moreover, MCU-JY-2.59 darkleo really improved the bass audio quality beyond any of stock JY MCU image files that I've tested to date, and even more so when combined with Viper4android and its highest quality audio driver.

Many thanks again.

Cheers,

R
[MTCB Hardware Development] JEMShoe:
What higher quality external mic are you using?
[MTCB Hardware Development] rhacy:
It's a Labtec pc voice mic, but I'm not sure of the exact model any longer. It did need 4 pole male to 3 pole female 3.5mm audio adapter in order to work as intended.

Best to all,

R
[MTCB Hardware Development] gb37270:
here I have made ​​the mod of the mic.

I disassembled my HU and soldered my jack on the Bluetooth Module.

when I tried to cut the 4th pin , I move a component on the Bluetooth card : ooops ! :(

I glued the component, fingers crossed.

like 4th pin was not too accessible , I remove the C102 that was before the bluetooth card (a bit into the unknown).

I put together the post , saying that bluetooth was dead :crying:

at boot , everything seems to work .

making a call and the sound is very good :laugh:

I 'm glad I made ​​the mod but I got a scare !
[MTCB Hardware Development] andyourdone:
Hey guys,

I am having this same issue as described in this thread (callers via bluetooth can barely hear me), and I want to try this mod. This is the product I have:

http://www.seicane.com/android-4-4-...-camera-steering-wheel-control-usb-sd-s018812

I would like to build my own external 3.5mm jack and run it to the back, and from there plug in an external mic. Before I remove the head unit and open her up, I want to make sure I do this correctly. I have a soldering iron and basic skills, can someone tell me what else need to complete this? Do I need to buy a 3.5mm jack, or can I use the end of a female 3.5mm plug and make my own connection?

Thanks!
[MTCB Hardware Development] TT_Vert:
so is this something that still must be done on the most recent HUs or does changing the bluetooth device to WQ_BC6b resolve this issue?

Thanks

Dave
[MTCB Hardware Development] Mekanix1:
Just another reason to disconnect the front mic from the BT module:

https://www.youtube.com/watch?v=Ap2JTcKpP6Q

In my case I connected the front mic directly to the BT board's ground or main board chassis ground and disconnected the ground line from the display board to the mic.

Now both mic's are alright sounding but I think mine is a special case. Its EMI interference comming from the screen. Grounding the screen's ground helped reduce the noise but only relocating the ground wire fixed it.
[MTCB Hardware Development] TT_Vert:
That sounds like RFI, so relocating the ground for the front speaker resolved, I assume you were on a call between that home phone and the HU? What happened if you pulled the phone away from the HU?

Dave
[MTCB Hardware Development] Mekanix1:
It was EMI, caused by the screen refreshing and somehow the ground between the main chassis and the display's chassis was pretty weak.

And yes I was in a call from the HU to my cell through bluetooth and then to my home phone.

On the HU side its all good and clear but on the home phone side all you hear is that noise which gets worse when I touch the screen or the home button.

The fix was to remove the negative for the built in mic. That made the rear mic work perfectly. But since I still wanted the functionality of the front mic I relocated the negative for the internal mic to the same ground plain as the main board and BT module.

I also added a substantial ground wire between the display board ground and the chassis ground as a way of bonding the whole unit.
[MTCB Hardware Development] TT_Vert:
Makes sense to me. Thanks for the info, I cannot believe how many oddities these things bring. Goes to show you the production tolerances in effect overseas.

Dave
[MTCB Hardware Development] Mekanix1:
Indeed! I actually sent it back to them and all they did was add a few capacitors to the positive line on the mic. No change though... I did end up calling them on it and they said I would get a %40 discount on a what ever else I wanted to buy from them. So at least they tried.

Oh and check out the added capacitors in the last pic.

Another thing I've added is the external wifi antenna connection.
[MTCB Hardware Development] TT_Vert:
So they add caps which change nothing and just send it back? Do they even test their "repairs"? Did you have wifi strength issues at some point?

Dave
[MTCB Hardware Development] Mekanix1:
Yeah they thought it was interference coming through the positive line so they tried to suppress it. I don't think they did anything really to test it. I had a few words with them but in the end I got it figured out so its all good now.

With the small wifi antenna inside the case I couldn't pickup wifi signals when I parked near a free wifi spot and in my shop only 20 feet from a router it would barely give any signal strength. So I added this to get a bit of a boost. So far its helped allot. I'd like to extend it outside the cabin though.

Haven't had much in-car time to test it lol its mostly on the bench with mods like this and rom updates :P
[MTCB Hardware Development] TT_Vert:
Where did you get the wifi bulkhead fitting and what external antenna are you using? I think I read you may be using a router wifi antenna? Did you do any before/after db gain testing?
[MTCB Hardware Development] Mekanix1:
I don't have any gain numbers. ( should have thought about that at the time) It was pretty much no signal to full signal.

This is what I used in the end.

http://www.ebay.ca/itm/WiFi-Antenna-3DBI-2-4GHz-with-U-FL-to-SMA-cable-CC3000-ESP8266-Arduino-ESP-07-/301696262776?hash=item463e7fa278:g:vLMAAOSwoudW4tVW
[MTCB Hardware Development] TT_Vert:
SO just having that antenna at the back of the HU in the dash increased it that much. What does this HU use for a default antenna or do I want to know? I'd like to install some remote sofware on the rom, like side sync or airdroid, to be able to do things to it remotely (wireless adb also) and having a strong wifi signal may come in handy for me.

Dave
[MTCB Hardware Development] Mekanix1:
A 3 inch peice of 24 gauge coax :(

That's all it was. Made a big enough difference for me switching to a real antenna.
[MTCB Hardware Development] TT_Vert:
Impressive. I wonder if two antennas would be better

http://www.amazon.com/gp/product/B0...na bulkhead&qid=1458512116&ref_=sr_1_1&sr=8-1

Do you by chance know how to disable the notification when someone quotes you? I don't see it in settings. Quite annoying when I've already subscribed to a thread.
[MTCB Hardware Development] Mekanix1:
I don't see it either.

I don't know how two antenna's would be better. If there was dual radio's maybe, but i'm not sure.
[MTCB Hardware Development] miaoudak:
pictures

Hello my friend.

can you posrt some pics of the mic modifications you have made?
[MTCB Hardware Development] anno_fi:
Does anyone have a connection scheme for bluetooth module GOC-I2U-705A

Or at least can tell me which pin to cut to get rid of internal mic
[MTCB Hardware Development] TT_Vert:
With mine I had to completely remove the STOCK internal Crappy mic. I then ran a wire from its PCB to the back for the mic. I have a parrot BT chip and a pumkpin HU. I found if I did not wire to the internal mic area I could not get voice recognition like ok google to work. IF I plugged into the back port I did get decent quality but again no ok google or voice searches. And look at first page anno and you'll have what you seek.

Dave
[MTCB Hardware Development] jakejm79:
So if I understand this correctly, the issue here is the external mic only works with BT and the internal works with both android apps and BT, so when you use BT w/ external it also picks up the sound from the internal mic, couple that with the poor routing of the circuitry which and interference. Has anyone though about desoldering the external mic jack and internal mic, soldering the external jack to the internal inputs, this would give you one external mic for both and no internal mic, should remove the reverb issue caused by two inputs on BT might still have the interference issue tho. I use voice search, etc way more than BT calling was wondering if there would be any downside to doing it this way?
[MTCB Hardware Development] TT_Vert:
Jake, that is what I did, sort of. I desoldered internal mic and soldered cat5 to the internal PCB to back of unit to a female 1/8" stereo bulkhead out the back to plug mic into. Wifey said it was crystal clear and all mic functions always work. I can OK google this way ;)

[IMG="1/8th stereo bulkhead"]http://ecx.images-amazon.com/images/I/71uHa8xDyXL._SL1500_.jpg[/IMG]

If you want it to look more professional
[MTCB Hardware Development] TT_Vert:
Have any of you tried a high quality microphone to help mitigate this problem?

Dave
[MTCB Hardware Development] anno_fi:
Thanks TT_Vert! I also removed the internal microphone and solded wiring and a 3.5 mm connection to the back of the unit - now it is near to perfect! Still some scratching noise now and then but overall good quality. I also get the same scratching sound when playing music over bluetooth so I think that has to do with something else - does anyone have an idea how to get rid of this?
[MTCB Hardware Development] jakejm79:
Thanks TT, yes "OK Google" is more important to me than BT call quality. I think what I will do is just desolder the external BT mic cable and solder it to the internal mic PCB solder points (after desolder the internal mic of course).
[MTCB Hardware Development] TT_Vert:
You should have both if you do what you are stating but it would probably be safer/easier just to extend wires to a female 3.5" jack at the back of the unit than desoldering the stock 3.5" jack and resoldering unless you are a very competent solderer.

Dave
[MTCB Hardware Development] jakejm79:
I'm pretty competent and I don't have a spare 3.5mm jack so I will give it a go, thanks.
[MTCB Hardware Development] TT_Vert:
Played around a bit today w/ a HU that was horrendous as far as mic quality. Was a joying unit. Ended up desoldering the internal speaker and just using the external with NO other modifications. I ended up using a mic from a pumpkin unit of all things as the joying mic still was kind of crappy IMO.. I was getting cutouts and i couldn't figure out wtf was going on. Ended up switching from the receiving call phone bluetooth earpiece to the speaker to test and that went away and the call quality was amazing. So I was partially chasing my tail this entire time using jawbone from wifeys receiving phone to test image quality. I could walk 15 feet from the mic and still hear myself pretty damn clearly. The only caveat here is the joying mic is wired strangely. It has a 4 contact 3.5" mic plus and the top two are for the mic. The pumpkin and most other mics I've seen are 3 so I had to modify a bit but nothing major. I'll take a pic of what I meant. The temp solder to the jack was for testing only. I'll end up soldering in a new set of 3.5" connections for this.

Joying mic:

Pumpkin mic:

Dave
[MTCB Hardware Development] Piaband:
Can you show the location of the internal mic pcb that you soldered to?
[MTCB Hardware Development] TT_Vert:
I can't right now. It is the board the internal mic is attached to. I suggest that you first try to desolder the internal mic from it's board and then try the external. That seems to work very well as well and it's a bit easier..

Dave
[MTCB Hardware Development] Nicolasfoto:
If you have the board with the C102 component, be very careful.. I removed the C102 and now have no Mic, not front or external. My Bluetooth module doesn't have any indication of which pin goes where so that could also be an issue.

Top:

3 by Nicolas van der Merwe, on Flickr

Back:

1 by Nicolas van der Merwe, on Flickr
[MTCB Hardware Development] Nicolasfoto:
Any help on which pin is which on this module?
[MTCB Hardware Development] warata:
Microphone fix at TD696A

Hello

I bought android HU which called Xtrons TD696A.

And this product has microphone problems too.

But I realize this HU has bit different to other pictures in this thread.

I wanted to upload pictures that inside of TD696A.

but forum admin doesn't allow to past pictures link.

so anyone know which capacita shouid I take off at this model?

give me an advice please.

invite me to more proper thread also welcome.

thanks!
[MTCB Hardware Development] halloj:
Why don't you just beep between solder-points of C102 and the BT-board? There's your connection for your external mic.
[MTCB Hardware Development] Nicolasfoto:
Hehe I wouldn't know how to do that.. I did find out what my fault was though. I stupidly thought I could use the earth from the board itself. When I soldered my negative to pin 5, everything worked again. I don't think there is much of an improvement though. Given the option I wouldn't do this mod on my unit.

I might try and fiddle with the Bluetooth settings and see if that improves anything.

Thanks for the help though.
[MTCB Hardware Development] SiteRnr:
Check for continuity with a meter. beeping as it was called. tells you if two places , wires or components are connected and allows you to trace a circuit. You can put one lead on on the bluetooth pin and then check around and locate the path for that pin to other components. with the other lead. Most meters the setting has a speaker or sound icon and when you connect the leads it will beep so you know you have the right setting.
[MTCB Hardware Development] Nicolasfoto:
Thank you.
[MTCB Hardware Development] Lyhaku:
New Revision of Klyde unit (model C-0255 1024x600 RK3188) - Renamed c32?

Hi,

I've a 2016 Pumpkin model C-0255 1024x600 RK3188 quad core (Klyde KLD6 v.2.85 and Malaysk latest firmware) and I have a horrible mic quality mic, both using internal and external mic.

I've tried the software mod suggested in this thread but my unit default bluetooth setting was already WQ_BC6B, so I tried to lower bluetooth volume to 0 but didn't work.

Now I'm going to try one of the hardware mods suggested here. But wich one Is better?

I bought 2 female mic jack, should I try first to desolder the internal mic and solder the new jack on the PCB? Or go directly to solder the mic to the bluetooch mobule and cut che C32?

Here come another issue, comparing your pic to mine it seems the C32 component you cut is called C7 on my unit.

Am I correct? Or it is another component and i should find the C32 in another position?

I'm not sure, and I would like to avoid cutting the wrong C...

The information printed on my unit board is KD-HCT-MB 2015/010/18 REV-3.3

Thank you

I can't add outside link to my post and I'm not able to upload pic here.. please use the links below to view my photos (remove spaces):

Pic 1: http : // i.imgur.com / tOqlUKF.jpg

Pic 2: http: // i.imgur.com / SXOjWr6.jpg

Pic 3: http: // imgur.com / myP2Hwp

Pic 4: http: // imgur.com / 7pKOOIA

Pic 5: http: // imgur.com / 8oBXX8V
[MTCB Hardware Development] TT_Vert:
IMO Just unsoldering the internal mic and using the external jack is sufficient. I've done it both ways w/ the same results at this point.

Dave