I have a 2007 HHR with approximately 140,000 miles on it. Recently, the Radio/Clock display began flickering some of the time. Other times it doesn't work at all and other times it works fine. Please don't tell me this is the beginning of some serious electrical issues!!!!

 

OK. More likely the radio or some wire to the radio is faulty.
Does the clock or radio lose it's memory? Could be a clue.
It is easy to get to the radio. Put your fingers in the A/C vent holes and give a good yank, then it's a couple of screws. Look for wires frayed not connected securely etc. especially ground wires.

 

My 2007 hhr does the same thing
I've got 81000

 

My 2007 HHR also began flickering from time to time. I took the dashboard panel off, unbolted the radio, and disconnected and reconnected the wiring harnesses. The display works perfectly now. Thanks for steering me in the right direction!

 

Low voltage will cause a similar issue. Since it's an intermittent problem, I'm with Donbrew. Check your connections, a shot of wd40 helps, contact cleaner would be even better.

 

Low voltage , dirt in the connections, and the original Barrett starting to head south! My 2007 started the same memory and flickering light show just before the battery bite the dust
Have your battery and charging system tested!
A battery lobotomy will reset the radio also.