Bluetooth & AllShare Dongle

[AC Question]

I have a GS3 that I have connected to an AppRadio 3 head unit. To take advantage of the screen mirroring/app usage I am using the AllShare Cast dongle. When I am connected to the dongle it forces media through that. Is there anyway of allowing the original bluetooth connection to override that? The dongle works well for the screen mirroring, but I find once I start adding audio to it, it just gets bogged down and starts stuttering.