Frame Rate Dropping when using Bluetooth headset on OS X

So this seems pretty narrow as a problem but it's been doing it ever since OS X updated to Sierra a few months back. I've searched for the a thread on this in Curse's but found nothing. I'm trying to figure where this is coming from but it only happens on LoL and no other games.

Basically after roughly 10-15 minutes of playing and everything going fine, the FPS suddenly drops from 130 to 20-40 with lag spikes. Comes back as soon as I close Curse.

iMac 5k late-2015 3.3GHz Intel i5 Radeon R9 M395 Beats Solo2 Wireless