so last summer I noticed a bug where when it is over 80° F and the car has been in the sun and is thoroughly heated up I will start it up and drive off and for the first few minutes of drive time (the hotter it is the longer this lasts) the radio will shut off whenever I step on he brake and then turn back on when step off the brake. Also, in between it will randomly shut off.
Has anyone else run into this before?

 

You have a short. Start chasing wires.

 

I had a similar problem with a MkIII Golf. Turned out to be a faulty ignition switch.

 

Had the same situation with my 2008 A3. The power door locks would also unlock/lock sporadically along with the radio problem. It was the ignition switch and your dealer should have a bulletin about it (mine did). Dealer replaced ignition switch and everything has been fine.

 

My radio works fine, but then automatically turns off after 1 hour, not a big deal as I can just turn it on again. I'm sure there must be a simple way of keeping it on all the time the ignition is on ??

 

If you're able to turn the radio on when the key hasn't been put in the ignition then it's a problem with the power feed. There will be two power feeds on the back of the radio; one for the radio station memory etc and one for the main power. Make sure they're both connected to the right supply. the main feed should be switched with the ignition.

 

"so last summer I noticed a bug where when it is over 80° F and the car has been in the sun and is thoroughly heated up I will start it up and drive off and for the first few minutes of drive time (the hotter it is the longer this lasts) the radio will shut off whenever I step on he brake and then turn back on when step off the brake. Also, in between it will randomly shut off.
Has anyone else run into this before? "

Same thing happened to me yesterday, while driving (2008 Audi A3) all of a sudden the radio goes off and the doors unlock. continue driving and it comes on again then off again. thought the car was going to shut down but it didn't. Is it really the ignition switch causing this?

Also been having the issue of my radio shutting down after 1 hour also. I just turn it back on.Took it to the dealer when it first started and they didn't fix it either.

Could the two issues be linked to the ignition switch?

 

White Audi A3 - what was the outcome of the issue? My newly acquired '09 A3 is doing exactly what your was doing. Brake - radio dies, let off it comes back on. The power locks are also activated in one direction or another when this happens.