I would hate to think that one lousy chip on a card is going to force me to pack it up and send it back to Meridian as it just came from there having just done the V4 upgrade.
I never did that. When Meridian worked with me to isolate what was going on, they direct-shipped me the replacement card. I put it in myself (trivial to pull the old and put in the new), retyped the unit according to their instructions, and that was that. Never had another problem.
Call Meridian if you're having problems. That's far more effective than posting here if you have a hardware problem.