To start, please don't assume that if no one responds, "no one wants to help" you.
First, please give a few more details. Sabayon version? video card? how did you install it, from emerge or something you downloaded somewhere? My apologies, I don't have q3 itself (i have open arena and used to have q3 for windows a loooong time ago
), so i don't know what some things are. also, if you didn't install via emerge, did you do it using sudo/root or not? this seems only slightly important, as it doesn't seem to make sense that some things would work and others would freeze if it were a permission problem, but it's worth asking anyway.
Next, please run your given game in konsole followed by > /home/YOURNAME/Desktop/errorstuff.txt or whatever you wish to call it. For instance, if youre running /usr/bin/et and your signin name is jack, then /usr/bin/et > /home/jack/Desktop/errorstuff.txt . When it freezes, hopefully whatever happened at the time of the crash (or perhaps even the cause of the crash itself) will be recorded in that text file. Noone has any clue what's causing your problems. Perhaps the info in that file can help, if it's recorded as I expect.
Lastly, the least likely answer from reading your posts.. if it didn't crash before the sound changes on a given map but does after like you seem to be saying, then ignore the rest of this post: If by "crashes" you mean your game freezes and the sound repeats over and over, I had a similar problem with UT04, but it happened a ways back when I was using Xlaunch and using ctrl+alt+f7 and ctrl+alt+f8 to switch between ut and my desktop windows alt+tab style.. it turned out to be a bug with the nvidia drivers. so, please, open nvidia-settings and under "X server information", please tell us what driver number you have. The newest ones fixed that issue for me, so perhaps if yours are old that could be why it "crashes".