Possible audio problem(s)
Think I stumbled upon an issue with the gcc and/or mpfr in F15. When I compile mplayer
and try to play mp3's or wmv files, I get high pitched distorted audio, almost screeching.
In F14, I do not get this problem. But in order to narrow down the issue, I updated the
GCC and related packages from 4.5.1-4 w/ mpfr 2.4.2-1 to the current F15 packages,
4.6.0-0.11 w/ mpfr 3.0.0 and re-compiled.. distortion and screeching occur. When I run
a distro-sync back to the F14 current packages and recompile, proper audio results.
Exact package names involved: cpp, gcc, gcc-c++, libgcc, libgcj, libgomp, libstdc++,
libstdc++-devel, libtool, mpfr.
Since mpfr and gcc versions are interlinked, I could not test them separately to see
if the problem was in the cause of one or the other. I'm wondering if someone else
can do some testing as well to verify this issue? You have to make sure you are testing
internal compiled mplayer libs, such as using its mp3lib library to play mp3's. I've tested
a bad build using other mp3 decoders built previous (libmad) and sound is fine then.
Seems to only be newly compiled codepaths using the new compiler packages.
---------- Post added 5th March 2011 at 12:09 AM ---------- Previous post was 4th March 2011 at 10:58 PM ----------
I still have the problem with the new 0.12 build. I don't think the problem is with mpfr as I did a
somewhat hackish forced downgrade of gcc/libstdc++ bits leaving mpfr and other bits alone. Broke
c++ stuff because of dependencies, but I could rebuild mplayer and get good audio as a test. So, at
least for my case, there is some kind of optimization in the 4.6.0 series causing me issues.
I'll have to experiment with -Ox settings and possibly building without sse code to see if that makes
a different, but will have to wait. I tried change runtine cpu detection and fast-memcpy settings to
Still not sure if this is only something with my setup or if nobody just does much compiling of their
own stuff anymore to notice these things.