Bluetooth problem on Raspberry Pi3

Hello everybody! I am running LibreElec 8.2.3 in a Raspberry Pi3. I recently bought a bluetooth 4.1 headphone and connected it without any problem to LibreELEC, but watching movies I experienced variable audio delays large enough (1 second or more) to unbearably annoy. I tried connecting the headphone to 2 computers running Win 10 64bit by means of a €8 USB bluetooth 4.0 adapter, and there was no audio delay watching the same movies. So I tried using the USB adapter on the Pi3 after disabling the onboard bluetooth, and the delay was gone forever (it seems).

So I would like to ask: is anything fundamentally wrong with the Pi3's onboard BT? Or might it be that it goes bananas because I also have a USB WiFi antenna and an OSMC remote connected to the Pi? I think that the power supply, which is an original Raspberry 2,5 ampere, is not to be blamed.

I would like to thank you all because reading this forum I learned a lot of things, and now my Pi3 and its LibreELEC run beautifully. Many heartfelt thanks also to the LibreELEC team! LE is really a great media center!

Thank you for the link, blueribb. In that post someone said that disabling the onboard Wifi solves the problem. I can't confirm this statement: since months my Pi's internal Wifi is disabled, I use an external Wifi USB adapter placed quite far from both the Pi and the TV (by means of a thick USB extension cable) to avoid interference and maximize the connection speed. Even with internal Wifi turned off, the onboard BT in my Pi3 seems to perform very badly with audio. My setup now works like a charm.

chewitt: Reading your posts I learned a lot about LE. Thank you! But defining "a little under par" pi3's BT and Wifi seems to me a big understatement!