2014-04-15, 19:40
@popcornmix. Nice work. Thanks.
tl;dr The i2s bus is sending out 32bit data but not initialising the data so it sounds like noise when 16bit audio is played.
I am using your build https://dl.dropboxusercontent.com/u/3669...fc6264.tar with paplayer for audio. I am using an ESS 9008 24 bit dac instead of the hifiberry. When I play a 16bit sound file full of silence on high amplification I hear lots of white noise. If I use a 24bit flac file I get pure silence, which is good and expected. I used a BusPirate to see that there are 32bits on the i2s bus but I can't read them with my hardware. I expect that the lowest 16 bits are not being initialised properly and end up with random data in them. The i2s control seems to be stuck on 32bits out of the pi. I didn't get anywhere trying to force alsa to 24bits in the asoundrc file. Any ideas?
tl;dr The i2s bus is sending out 32bit data but not initialising the data so it sounds like noise when 16bit audio is played.
I am using your build https://dl.dropboxusercontent.com/u/3669...fc6264.tar with paplayer for audio. I am using an ESS 9008 24 bit dac instead of the hifiberry. When I play a 16bit sound file full of silence on high amplification I hear lots of white noise. If I use a 24bit flac file I get pure silence, which is good and expected. I used a BusPirate to see that there are 32bits on the i2s bus but I can't read them with my hardware. I expect that the lowest 16 bits are not being initialised properly and end up with random data in them. The i2s control seems to be stuck on 32bits out of the pi. I didn't get anywhere trying to force alsa to 24bits in the asoundrc file. Any ideas?
