Front driver side 2 speakers only work with phone/nav，not radio!

So long story short. I have 2010 Prius package V, JBL. Recently 2 of front driver side speakers stop working(1 on dash,1 on door) only when I listen to radio and stream music from my iphone. I played with the L/R F/R balance and made sure about it.

However when I got phone call and using navigation guidance voice it works no problem.

Just want to get some idea, may it be some loose wire problem? Are radio wire and Bluetooth/navi wire running same source? Or the worst case the unit is damaged inside? What can I do about it? Dealer??

Anyone has any idea about this please help! I'm deeply appreciated!

The unit is oem E7022 in the photo.

 

Anyone help pls!!!