ZJones

Since GM seems to offer zero solutions, what seems to have resolved our maximum volume problem is — checking or replacing your BATTERY. We noticed this cranked up volume issue coincided with our problems about 30 minutes later starting our 2014 GMC Sierra 1500. The “factory reset” of the radio suggested on another site failed. So—we changed the battery the same day and—we have NO volume control issues at all now. Thankfully—since we were without tools, the O’Reilly Auto Parts store near us had our battery in stock (pricey at $200), BUT their staff tackled the complex and tedious battery change for us. ‘Hope this helps some of you folks.