Radio has no sound. 2015 silverado

[Unlimited]

For the past 4 months I've been having problems with the radio.  When I start the truck the radio and clock never works in the beginning.  It usually took about 10 to 20 minutes before the sound would work.  The clock would never display either, but just before the sound would come on, the clock would display the time.  The navigation would work always, but you would have to use the touchscreen to get it to work.  Very frustrating to say the least! Now it doesnt seem to work at all.  Looking for advice.  Already tried removing the fuse and wiggling the hmi wires.  Any other thoughts?  Thanks.

[PMurray]

If navigation doesn't work, be thankful.  Last week while on the Kansas Turnpike, I requested Turn by Turn to the nearest hospital (real, honest emergency).  They directed me to a group of cattle pens just a few miles ahead. The nearest hospital was still about 40 miles away.

[Paintor]

It’s electrical. There are videos on how to pull the top of the dash apart to fix the ground wires by the windshield pillars.

 

GM replaced my radio. Still crashes and resets while driving. They cant fix it.

[xjjosh]

It has happened to me before when the battery voltage got low. System turns of the speakers until battery is sufficiently charged FWIW.

[Unlimited]

Removed part of the dash and cleaned the grounds by the pillars, but the problem still exists.  Will take battery in next to have it tested.  Any other thoughts?  

[Unlimited]

Battery tested ok.  Any additional suggestions?