Car Play issues with IOS18-IPhone 13 pro

Car Play is not working properly since IOS18 update. When I plug in my phone, music is playing through my front speakers and not all speakers in my Chevrolet Tahoe. If I try to adjust the volume, its displays as voice instead of audio. I have tried different usb outlets in truck and cords, and it has not corrected the issue. The music will play for 30 minutes or so, and then it will pause and switch to playing in all speakers. I have deleted my phone from car play and added it back. Some times it connects to Bluetooth and sometimes it doesn't. I did not have this issue prior to IOS18 update.