That sounds like a kernel issue. Are you wiping between ROM swaps? If not, try that, or make sure it's at least twice/three times for each cache and system data. If you are already doing that, try installing a new kernel. To do that, enable USB mass storage in recovery and then copy a kernel to the SD card. Install it the same way you did the ROM and then try to reboot again.
I'd recommend the following kernel.
If that works, you're good and should try a more aggressive kernel (so Flash can play because Flash requires an 800MHz processor speed and that one I linked to tops out at 600), but make sure it's standard/medium voltage.
If that doesn't work either I'll try to help more (and offer more detailed instructions if you can't figure out what I'm talking about above). Good luck!