On Mon, 27.04.09 18:53, Daniel Mack (daniel at caiaq.de) wrote: > > > 'aplay -Dplughw foo.wav', it is clearly audible that PA adds some kind > > > of amplification to the material (I would guess ~3dB), even though all > > > GUI accessible levels are set to 100%. > > > > > > The driver I'm working on does not have any volume control features, > > > hence this must be done in software. > > > > > > Has that been encountered before? > > > > Please try to reproduce this, then do "ls" in pacmd and paste it > > somehere. This should show if PA does digital amplification for any of > > the active streams. > > It's always reproducable, here is the output: > > http://caiaq.de/download/tmp/pacmd-distortion.txt > > Let me know if I can provide more details. Hmm, that output suggests everything is in order. Both the sink and the stream are fixed to 0dB so PA shouldn't touch the data at all, just pass it through to the device. Hmm, what makes me wonder though is the 's24be' sample format. There might be something wrong with the conversion code for that. s24be is 24 bit packed big endian. Is that really the native sampling format of the device? (Hmm, ich weiss ja nicht, was das genau f?r nen Device ist, aber wenn Ihr das Dingen kurz nach Friedrichshain ausleihen wollt, dann schau ich's mir mal an und fix Euch den Converter-code ;-)) Lennart -- Lennart Poettering Red Hat, Inc. lennart [at] poettering [dot] net ICQ# 11060553 http://0pointer.net/lennart/ GnuPG 0x1A015CC4
