A2DP fix for media: Currently CM10(CyanogenMod JB) based builds the Bluetooth device works just to stream audio to make calls but it doesn't work when streaming media(Pandora, PowerAmp Music player)
Looks like sample rate is missing in the at a2dp line in the "audio_policy.conf"(/etc) line "sampling_rates 48000" and the 44100 needs to added before the 48000 with this "|" symbol and it should look like this "sampling_rates 44100|48000".
After changing the sampling rate reboot your device in order for it to take effect.
Edit file with root explorer text editor.
The fix is for Hercules/Skyrocket CMX based builds:
- AOKP JB
File is located at root of system you can use Root Browser or Solid Explorer and open as Text Editor to edit. Make a back up of the file just in case.
Root Browser Lite:
Edit Sept-17-2012 10:14pm:
As of Sept17+ some builds have been implemented with the fix by the OPs, not sure if CyanogenMod has done it yet.
Edit Sept-19-2012 11:04pm: Fix has been implemented by CyanogenMod, it looks like the 48000 sampling rate is not required. I've tested it too and all audio works(with just 44100) except during calls and plays the audio on earpiece of the phone/device instead of streaming it to BT earphones. See Post by budjb.
××× Workaround ×××
I notice that during a call if you turn OFF the Bluetooth earphone while connected to your device(phone) then turn ON the BT earphone it'll connect and also stream the phone call to BT earphone. :screwy:
I can confirm that bluetooth audio and calls work on the sept 13th build. By default, that build's audio_policy.conf has a2dp's sampling rate set to 48000, which does not work, however changing the rate to 44100 allows both audio streaming and calls to work. Having both rates (44100|48000) does not work, it has to be only 44100.
This exact same config that works on the 13th does not work on the 17th or 18th builds. On those builds, I can get audio streaming to work but not calls over bluetooth. On those builds, calls will only play through the phone's speaker with the sampling rate set only to 44100. When I add 48000, audio streaming still works, and calls no longer play out of the phone's speaker while bluetooth is connected, however, the stream to the bluetooth device is completely silent.
So looks like something broke between the 13th build and anything after. Hope this helps, and hope you can fix it!
Info about sampling rates: 44,100 Hz Audio CD, also most commonly used with MPEG-1 audio (VCD, SVCD, MP3). Originally chosen by Sony because it could be recorded on modified video equipment running at either 25 frames per second (PAL) or 30 frame/s (using an NTSC monochrome video recorder) and cover the 20*kHz bandwidth thought necessary to match professional analog recording equipment of the time. A PCM adaptor would fit digital audio samples into the analog video channel of, for example, PAL video tapes using 588 lines by 3 samples by 25 frames per second. Much pro audio gear uses (or is able to select) 44.1*kHz sampling, including mixers, EQs, compressors, reverb, crossovers, recording devices and CD-quality encrypted wireless microphones. 48,000 Hz The standard audio sampling rate used by professional digital video equipment such as tape recorders, video servers, vision mixers and so on. This rate was chosen because it could deliver a 22*kHz frequency response and work with 29.97 frames per second NTSC video - as well as 25 frame/s, 30 frame/s and 24 frame/s systems. With 29.97 frame/s systems it is necessary to handle 1601.6 audio samples per frame delivering an integer number of audio samples only every fifth video frame. Also used for sound with consumer video formats like DV, digital TV, DVD, and films. The professional Serial Digital Interface (SDI) and High-definition Serial Digital Interface (HD-SDI) used to connect broadcast television equipment together uses this audio sampling frequency. Much professional audio gear uses (or is able to select) 48*kHz sampling, including mixers, EQs, compressors, reverb, crossovers and recording devices such as DAT.
Sent from my ♛ SGH-T989 ♛ w/CM10-Hybrid PA v2.14(9-22-12) by: michinohatoresu using XDA app.