Vizio 46" won't display from MacBook using miniDisplay to HDMI--used to tho!!!

That about sums it up. I'm running Lion and about to update to Mountain Lion. I've tried PRAM reset, using disk utility--repairing the permissions and disk, &disk warrior. Random combinations of unplugging HDMI cables and turning off and on the computer have elicited random positive results. It was even working consistently yesterdayuntil I let the computer go to sleep. Now the TV says "No Signal" or "Not Support". Ive repeated the same processes to no avail. iIeven tried SwitchResX after reading these topics.

I'm convinced its a software issue as the cables currently work with other computers and they used to work fine with the MacBook. There are a bunch of similar topics that have been largely gripe sessions. I'd like to get to a solution. I use the TV for entertainment (duh) but also as an extended area for more real estate when doing music production. I'm in a creative slump, so I'm neurotically trying to fix this.