Bluetooth is the shortest-range, most interference-prone link in your rack, and an AVR (a metal box in a cabinet below the TV) is about the worst-placed device to receive it. So the fixes are mostly about the obstacle course, and the last fix is to stop using it.
What helps, in order. Clear the pairing and pair fresh: delete the AVR from the phone and delete the phone from the AVR's Bluetooth menu, both sides. Stale pairings cause most "won't connect" cases and half the dropouts. Reduce the obstacle course: a closed cabinet with metal and glass weakens the signal meaningfully; even leaving the door open helps, and if the AVR sits behind a tinted glass door in a wall unit, that door is your problem. Move Wi-Fi congestion away: 2.4 GHz Wi-Fi and Bluetooth share the same spectrum, so a router sitting on the same rack is a reliable source of intermittent dropouts. Keep the phone in the room; walking to the kitchen with the phone in your pocket is a range test, and the AVR usually fails it.
That covers troubleshooting. Now the part I would actually say to a friend: Bluetooth is the convenience input, not the quality one. It compresses the audio, it is fussy about distance, and it ties the music to whoever's phone it is. The AVR's network streaming (AirPlay, Chromecast, the brand's own app, or Spotify Connect and its cousins) sends the stream over Wi-Fi to the receiver, drops far less, and sounds better because nothing is being squeezed twice.
Can Bluetooth be made to behave? Usually. Is it worth the effort once you have heard the network path from the same receiver? Rarely.
If your listening has outgrown Bluetooth's patience, the better path is almost certainly already built into the AVR you own, at no cost. Tell us the model and I will point you at which streaming route it supports.
Not sure what fits your room and budget? Share your room size and budget on WhatsApp. It is a two-minute answer with a floor plan.
