I have iOS 12.3.1 and still same problem. My dealership maintenance department tells me it’s a wide known issue, but GM has yet to fix it. My 2016 Silverado did not do this. I have noticed this radio seems to somehow take complete control over my phone volume. The phone thinks this radio is a pair of Bluetooth headphones and not a radio. I can adjust the volume on my radio and watch the volume icon on my phone change. Whatever is causing this, it needs to be fixed ASAP. I’m still thinking it’s the truck radio.
I have iOS 12.3.1 and still same problem. My dealership maintenance department tells me it’s a wide known issue, but GM has yet to fix it. My 2016 Silverado did not do this. I have noticed this radio seems to somehow take complete control over my phone volume. The phone thinks this radio is a pair of Bluetooth headphones and not a radio. I can adjust the volume on my radio and watch the volume icon on my phone change. Whatever is causing this, it needs to be fixed ASAP. I’m still thinking it’s the truck radio.