Terrible 2.4ghz WIFI speeds when bluetooth enabled

I've only been noticing this since 2 weeks, and I've found other threads on oneplus forums/reddit that have the same problem, but appearantly nobody knows a fix. When I have bluetooth enabled on my OPO the WIFI speeds on 2.4ghz go down to 100-200 kB/s max. 5Ghz seems to be unaffected, but I don't have that everywhere. I was using CM12.1 official when I first noticed it happening. When I turn off my bluetooth the wifi speed goes back to what it's supposed to be, but I have a Pebble so permanently disabling bluetooth isn't really an option for me... I've installed Sultanxda's [ROM+KERNEL][5.1.1] Unofficial CyanogenMod 12.1 with CAF 3.4.0 kernel [Oct. 11, 2015] today but the problem persisted. I then tried the newest AK CAF kernel but again to no avail. What else could I try? Or has anyone found a fix by now?

Thanks for your time!