Problems with keeping music on with screen shut

[Procter]

I started to use slacker and other online streaming music source more often recently, and found out two cabs to enable music when shutting down the phone screen.

Keep_Music_playing_registry.cab and KeepMusicOnWhenIdle.cab were both found at here and xda.

However, the 1st cab never worked for me and it had some conflicts with 2nd cab so that when the two were both installed, my phone could not be waked up by pushing the power button.

So I cleared out the 1st cab and installed the 2nd one only and it worked like a charm. But just now when I answered a phone call through my wired headset (it has mic), the registry setting did not work any more. Music from slacker stopped whenever I pushed the power button to shut down screen. I had to reinstall the cab to get this function back. I haven't tried again with my headset yet. But has anyone had similar experience? Is there a way to permanently set the music to be on with phone screen shut?

Thanks a lot.