I'm trying to use all 4 input channels on a MAudio Quattro on Fedora Core 5 running on a Playstation 3 (PPC build of the kernel with some stuff stripped out). The final app will just use open() and read() to process the data directly. In that application it looks like I get 2 copies of the first 2 channels. I get Channel 0 replicated in Channel 2 with exactly the same values, and Channel 1 replicated in Channel 3. (Recording 16 bit at 44.1kHz) I followed the directions in http://wiki.linuxquestions.org/wiki/M-Audio_Quattro to setup .asoundrc. I am trying to debug using just arecord but I can't get it to do anything arecord -r 44100 -c 4 -f s16_le -D q4 -d 5 test4.wav gives me arecord: xrun:1082: read/write error, state = PREPARED Any help would be appreciated. Thanks, Jim Steed Here is the relevant part of /proc/bus/usb/devices: T: Bus=01 Lev=02 Prnt=02 Port=01 Cnt=02 Dev#= 4 Spd=12 MxCh= 0 D: Ver= 1.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1 P: Vendor=0763 ProdID=2001 Rev= 1.05 S: Manufacturer=M Audio S: Product=USB Audio Quattro C:* #Ifs=10 Cfg#= 1 Atr=40 MxPwr= 0mA I: If#= 0 Alt= 0 #EPs= 0 Cls=01(audio) Sub=01 Prot=00 Driver=snd-usb-audio I: If#= 1 Alt= 0 #EPs= 0 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio I: If#= 1 Alt= 4 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio E: Ad=03(O) Atr=09(Isoc) MxPS= 192 Ivl=1ms I: If#= 2 Alt= 0 #EPs= 0 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio I: If#= 2 Alt= 4 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio E: Ad=85(I) Atr=0d(Isoc) MxPS= 192 Ivl=1ms I: If#= 3 Alt= 0 #EPs= 0 Cls=01(audio) Sub=01 Prot=00 Driver=snd-usb-audio I: If#= 4 Alt= 0 #EPs= 0 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio I: If#= 4 Alt= 1 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio E: Ad=03(O) Atr=09(Isoc) MxPS= 576 Ivl=1ms I: If#= 4 Alt= 3 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio E: Ad=03(O) Atr=09(Isoc) MxPS= 288 Ivl=1ms I: If#= 4 Alt= 4 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio E: Ad=03(O) Atr=09(Isoc) MxPS= 192 Ivl=1ms I: If#= 5 Alt= 0 #EPs= 0 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio I: If#= 5 Alt= 1 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio E: Ad=85(I) Atr=0d(Isoc) MxPS= 576 Ivl=1ms I: If#= 5 Alt= 3 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio E: Ad=85(I) Atr=0d(Isoc) MxPS= 288 Ivl=1ms I: If#= 5 Alt= 4 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio E: Ad=85(I) Atr=0d(Isoc) MxPS= 192 Ivl=1ms I: If#= 6 Alt= 0 #EPs= 0 Cls=01(audio) Sub=01 Prot=00 Driver=snd-usb-audio I: If#= 7 Alt= 0 #EPs= 0 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio I: If#= 7 Alt= 1 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio E: Ad=04(O) Atr=09(Isoc) MxPS= 576 Ivl=1ms I: If#= 7 Alt= 3 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio E: Ad=04(O) Atr=09(Isoc) MxPS= 288 Ivl=1ms I: If#= 7 Alt= 4 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio E: Ad=04(O) Atr=09(Isoc) MxPS= 192 Ivl=1ms I: If#= 8 Alt= 0 #EPs= 0 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio I: If#= 8 Alt= 1 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio E: Ad=86(I) Atr=0d(Isoc) MxPS= 576 Ivl=1ms I: If#= 8 Alt= 3 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio E: Ad=86(I) Atr=0d(Isoc) MxPS= 288 Ivl=1ms I: If#= 8 Alt= 4 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio E: Ad=86(I) Atr=0d(Isoc) MxPS= 192 Ivl=1ms I: If#= 9 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=snd-usb-audio E: Ad=81(I) Atr=03(Int.) MxPS= 32 Ivl=1ms E: Ad=82(I) Atr=02(Bulk) MxPS= 32 Ivl=0ms E: Ad=02(O) Atr=02(Bulk) MxPS= 32 Ivl=0ms
