For the past couple of weeks, my Bluetooth mouse and headphones have been randomly disconnecting from my desktop PC. Sometimes they reconnect after a short while, but other times they stay disconnected. It happens regardless of what the computer is doing, and the issue is becoming extremely frustrating. I've already tried forgetting and re-pairing the devices, disabling power management for the Bluetooth adapter, updating the Bluetooth and device drivers, updating the BIOS, reinstalling the Bluetooth drivers, and a few less scientific troubleshooting methods. Nothing has provided a lasting fix. The PC is a tower with built-in Bluetooth, specifically a Legion T3.
1 Answer
First, check that the external Wi-Fi/Bluetooth antennas are firmly connected to the coax ports on the motherboard. Missing or loose antennas are a surprisingly common cause of unreliable Bluetooth on desktop systems, especially for mice and headphones.

The antennas are connected. I also tested with them removed, and the disconnecting still happened, so that doesn’t seem to be the cause here.