Iphone 11 bluetooth crackling, poor bass. Sounds as though speakers are defective. Is this the solution?

My bluetooth connection suddenly became noisy and kinda crackly. Also under sonic load, the bass would become really lumpy and it sounded as though my speakers were damaged. I realised it was the same issue whichever device I connected to. I saw lots of similar posts here, and found no useful solution.

I spent a long time on the phone to Apple support and eventually this rectified it for me:

Reset Network settings

(settings general reset, reset network settings)

It now works as it should. I hope others benefit from this fix.