Just installed anew 550 plus I’m the car was testing it out and the volume seems to not go very high. Hooked it up directly to the second battery, but still the volume is low at wide open any suggestions.
Is the volume low with both car to car transmissions and intercom between passenger and driver ? if so the problem is most likely with the intercom. I had the this issue with a 660 plus and had to return it to Rugged for replacement, problem solved !
I ran into this recently on my 696. It was caused by the vox being too high/sensitive, so ambient noise attenuated the music volume and kept it low. Try turning down the vox and see if the music gets louder. At high speeds you'll likely have to turn vox down a bit to fight the wind noise triggering the mics.