Audio Not Working after 11.6" Display Switch

Hey all - need some help! I have a 2020 Prime XLE, and cracked the Infotainment Screen (E7057). It was still working - side buttons still controlled volume and temp, and the map updated - but the touch controls were dead.

I bought a replacement unit (E7052 with JBL) and the install went great! I swapped the Micro SD card from the old unit into the new unit, patched all the cables on the back properly, and did the long software update. However, while everything works with the new unit (Nav, Bluetooth connection, touch controls), there is no audio coming out of the speakers. It perpetually says "Audio Off" and when I try to select a source, it will flash and stay on the selection screen. Sometimes I can hear a brief (1/2 second) static through the speakers when i try to select FM / AM, but that's it. The Bluetooth shows a connection and I did a test call with my wife where she could hear me (so the mic works) but I couldn't hear her.

Any thoughts or tips? I don't think the part is defective but working with the vendor to confirm that. Thanks!