I bought cheap P47 bluetooth headphones. But they constantly have some background noise, which is unbearable. The sound differs on events like bluetooth pairing, and when my laptop's CPU usage changes.
So, I tried on a different computer (desktop), with a bluetooth dongle, disabling the other playback and recording devices, disabling the wifi in the room... The noise is still present.
As more, there is a high-pitched noise when sound is playing, typical of a low-quality sound encoding, presumably happening for the bluetooth transmission.
My question is: if I buy less cheap headphones (but still low budget...), will I encounter the same issue? Would there still be a background noise, though quieter? I'm very sound-sensitive, so I would really need something with no background sound at all.