Of course you could always just turn the music off and have your own created playlist play on the side in WMP, or what ever player you have. Make it easy on yourself?
I understand that injecting your own created music into thug 2 would make it that much more personal... and having the ability to change the music in the background as soon as a new TA starts is much more appeasing... but the same can be done simply by creating your own playlist in WMP and just hitting the skip buttons on a media keyboard. Or assigning a macro for your computer to understand to quickly switch a track whilst in another app...