Yes. It's just as annoying as when the broadcasters bump up the volume a few dBs during commercials. It would be nice if VOOM, cable and the broadcast network were on the same sheet of music, but I have always has audio discrepancies to various degrees no matter if it were sat, cable or OTA.
Anyway, your TV will most likely have settings to automatically reduce loud passages and boost soft passages to more uniform loudness or automatically equalize the volume level of programs containing significant level differences from one segment to another (for example, regular programming to commercials). These are fine for normal programming, but you will want disable these setting when listening to music and watching movies with special effects. In this case, I just hit mute on the TV and turn on the HT Receiver. Also, your TV may processing sound differently depending on the input: (I'll use my sets for example)
Mits - works the best with firewire, DTV (ATSC/QAM) and NTSC input, doesn't do nearly as well with VOOM over component...I often manually adjust volume on certain channels.
Samsung (auto sound feature) - does an adequate job with VOOM (DVI).
Sony (Steady Sound feature) does an excellent job for VOOM (Component) and other inputs as well.
Anyway, contact VOOM Customer Support
http://voom.custhelp.com/cgi-bin/voom.cfg/php/enduser/cci/std_cont.php?page=null and make sound adjustments on your set. I hope this helps.