iOS and Harley Davidson Boom 4.3 USB vs Bluetooth

[HDBoy]

Plan

Premium

Country

Canada

Device

iPhone 8

Operating System

iOS 12.3.2

My Question or Issue

So I have an 8plus, with 12.3.2.  I can hook up with HD Boom 4.3 via Bluetooth all works well, but I cannot via USB.  When I hook up via USB the HD Box say no media found on device.  I have an iphone 4 iOS ver 9.3.5 which I can hook up via USB and it works great.  I'm sure it's Apple thats done something in later versions of their OS to mess with this, just wondering if there is something I can try to get my 8+ to work via USB since the sound is louder via USB.  If not is there something that can be done with the app that can remedy this?  Oh and its the same thing in my Dodge RAM 1500 with their infotainment system (called uconnect).

[zchopper62]

i own a 2014 street glide and can get my iphone 5 to partially work. meaning i can only get the playlist that i select off the iphone but have no functionality in selecting anything via the HD BoomBox 6.5 GT. When i did use iTunes it worked flawlessly and don't understand why spotify will not work?? i have placed a call with my local HD dealership to see if they can shed some light and if spotify can help well great but won't hold my breath.