Doing a simple "cdparanoia -v -d /dev/cdrom 1 test.wav" produces a silent wav-file. I tried the stable amd64 version and the masked one. Both the same.
As that version is dated from 2001 (on the homepage of cdparanoia) I tried the current svn. It was working fine! So it would perhaps be better to choose that one.
Created attachment 89415 [details]
output of cdparanoia, hexdump of wav and emerge --info
Seems like an incompatibility with your CD Reader. Unfortunately cdparanoia hasn't released anything recently, so you'll have to use some other software. dev-libs/libcdio installs a fork of cdparanoia, too.
I just was at http://www.xiph.org/paranoia/ and saw "Current test version: cdparanoia III 10pre0" its dated from the end of august so far after my initial report. This one as well as the svn one is working.