Twice within the first 6000 miles my check engine light has come on with the 'Service Emmision System' message. First time at about 2000 miles the service department apparently just reset it the system and no issues until 4000 miles later, hopefully the second time they fix the problem.
Had the unresponsive radio issues with my 2020 1500 Duramax HC during one a trip with multiple stops. Radio started working later the day but then the browse FM stations function wouldn't pickup any stations. Plan to take it to the dealer for the first oil change to have them look at the radio.