A few here may remember an old thread on mm I started about my crappy electrics in my current car, and that I suspected it was a ground look issue.
Well yesterday a freind mentioned you can by ground loop isolators. So I picked on on Amazon and 15months on, the issue is fixed, no hum coming though the car speakers, when my phone is charging and outputting sound to the cars speakers.
Also my pc has a similar issue to a lesser degree, and I’ll be getting a second.
Ltd fix cost me a whole £8
3.5mm Jack Ground Loop Isolator, HAVIT Car Speaker Noise Filter, Home Stereo with Audio Cable (HV-X2, Black) https://www.amazon.co.uk/dp/B01IETQQQK/ref=cm_sw_r_cp_apa_WGnOybR1GN96M