Intermittent "No audio and intermittent ac/heater blower issues. Need advice

[slfrederick]

2015 Chevy Silverado 1500 4x4 purchased last year with just over 50k miles.  Shortly after I purchased the truck I started being plagued by these two ghosts.  First issue is an intermittent no audio in the cab on start up.  No audio from My Link, radio or anything else in the cab.  Usually corrects after a restart but not always.  Second issue is the ac/heater blower occasionally will start cycling the speed up and down.  It will go all the way down for a few seconds then all the way up or somewhere in between, changing constantly until I stop the truck and restart.  There's no way the blower should be acting like this.  Neither of these is a huge issue but I'd like to solve the problem.  I scheduled the truck to go in for a recall next Monday and asked the service guy about these two issues.  He said he could find no service bulletins on the issues and hadn't personally heard of them before.  So what should I do now.  They don't seem to want to mess with it.  Thanks in advance Steve