Vinod Koul <vinod.koul <at> intel.com> writes:
The sound is a bit distorted tho, I can alleviate this effect by lowering the values of these controls:
- codec_out0 Gain0
- media1_in Gain0
- pcm0_in Gain0
but the distortions do not go completely away, and they are not present in Android even at the highest volume.
I dont think the gain is causing the distortion. It can be SSP settings DO you see distortion in one channel or both (try with headset)
Hi Vinod,
I've been following this thread since a while and trying out the various things suggested. I have an Acer Aspire Switch 10 which seems to have the same audio chip like the Teclast and the other tablets mentioned in the bugzilla thread. I also had to change the interrupt index and tried the other driver with the fw_sst_0f28.bin-48kHz_i2s_master firmware, got overheating etc. etc. Finally following the advice in this thread I got to the same point, mfld driver with ssp0 firmware and applying the alsa settings as in
http://mailman.alsa-project.org/pipermail/alsa-devel/2015-June/094080.html
I get the distorted sound. I've been playing around with the mixer controls and wanted to report back my findings, maybe it can help. What I've found:
1) Sound seems only to be coming from the right speaker. If I turn off "Speaker R" there's no sound. Turning off "Speaker L" doesn't seem to do anything. If I turn off both playback stalls. Generally If I turn off any of the setting suggested in your mail playback stalls (mplayer).
2) By turning on "HPO MIX DAC1" "HPO MIX DAC2" "HP L" and "HP R" I get sound from the headset. Here also the sound is distorted and is only coming from the right channel.
3) Volume controls "Headphone" "Speaker" have no effect (I can't turn off the volume).
My kernel is: 4.1.0
Modules:
$ lsmod | grep snd
snd_soc_sst_bytcr_rt5640 16384 0 snd_soc_rt5640 86016 1 snd_soc_rl6231 16384 1 snd_soc_rt5640 regmap_i2c 16384 1 snd_soc_rt5640 snd_intel_sst_acpi 16384 1 snd_intel_sst_core 69632 1 snd_intel_sst_acpi snd_soc_sst_mfld_platform 69632 3 snd_intel_sst_core snd_soc_core 155648 4 snd_soc_rt5640,snd_soc_sst_mfld_platform,snd_soc_sst_bytcr_rt5640 snd_compress 20480 1 snd_soc_core snd_pcm 106496 4 snd_soc_rt5640,snd_soc_core,snd_soc_sst_mfld_platform,snd_soc_sst_bytcr_rt5640 snd_timer 28672 1 snd_pcm snd 69632 7 snd_soc_core,snd_timer,snd_pcm,snd_soc_sst_mfld_platform,snd_compress soundcore 16384 1 snd
alsa.state is "baytrailcraudio" with the setting suggested in your mail.
I hope this info will be helpful!
regards Istvan