Bluetooth Audio Cuts Out Randomly on My OnePlus 9 Pro During Calls

I’ve been using my OnePlus 9 Pro for about a year now, mostly loving it, but recently I’ve noticed a frustrating problem when I make phone calls using Bluetooth headphones. The audio will randomly cut out for a few seconds, then come back. This happens regardless of the Bluetooth device I use - tried both my Sony WH-1000XM4 and my car’s infotainment system. I’ve already updated to the latest OxygenOS version, reset network settings, and even cleared Bluetooth cache, but no luck. WiFi and other Bluetooth functions work fine, and the issue only happens during calls, not when streaming music. Has anyone else faced something similar with the OnePlus 9 Pro or newer models? Is there a known fix or a workaround to keep call audio stable over Bluetooth? Would switching to a different dialer app help, or is this more of a firmware issue?