I've found some info when installing ALSA in my Gentoo that may be usefull for the ALSA Guide: when I first installed the default portage ALSA (I guess it's 0.9.2), OSS emulation was really noisy altought pure alsa aplications did work fine. I've tried installing the 0.9.6 version but the problem remained. After a few hours of google search, i've found the problem... there is a feature in ALSA that makes OSS Emulation use /dev/dsp with alsa's 4-channel output and /dev/adsp with the normal output but this stuff is kinda broken for some cards. The workaround is to tell alsa oss emulation to flip those, by adding: "options snd-pcm-oss dsp_map=1" to /etc/modules.d/alsa (actually you're saying that /dev/dsp is the 2nd alsa output) In my case the bug could also be corrected by changing a set in my card: "options snd-via82xx enable=1 dxs_support=0" in /etc/modules.d/alsa just for records, I own a A7V8X-X motherboard, onboard sound card. Anyway, I think it would be useful for people installing ALSA knowing that this stuff may happen. IMHO, I think a chapter should be added in the Final Notes about it. Specially to warn people that they should test ALSA with pure alsa software, and only after this moving to oss-emulated stuff. Reproducible: Always Steps to Reproduce: 1. Installing ALSA drivers 2. Using ESD over OSS-Emulation Actual Results: The output sound is noisy.
Created attachment 18749 [details, diff] Patch to fix oss emulation issues (including note to add "oss" to USE)
but you'll have to define +<e>oss</e> in your USE-variable too. how about "only if you define <e>oss</c> in your USE-variable."? the rest looks good
perfect to me.
Created attachment 18795 [details, diff] New patch to please BennyC :-)
patch looks good :D
committed
