Having just run clamav over my whole system, lame-3.97.tar.gz in /usr/portage/distfiles as a PUA. Not sure if this means anything, but I thought I should report it. Reproducible: Always Steps to Reproduce: 1. run clamav over distfiles 2. 3. I'm reporting this to clamav as well.
This isn't a Gentoo specific problem. Your three choices are to complain to the media-sound/lame upstream developers, complain to the app-antivirus/clamav upstream developers, or to prove that $SOME_OTHER_DISTRO with the same version of clamav does not find lame-3.97.tar.gz to be a "PUA". If you find you can do the latter, then please reopen this bug.