Channel Master CM-7500 DVR+ clock issues
 

Maybe this might help someone in the future

I replaced IC marked U5, MCP7940M-I/SN (58 cents @ Mouser) and it is now keeping perfect time.

There are extremely small components very close to each end. So much so I didn't feel comfortable using a hot air gun (even taping off everything but the chip) or bathing the chip in solder. I had an idea which might be common; I used a sharp razor blade to cut all 8 leads, removed the individual leads with a solder tip and soldered in the new chip.