I upgraded my imac 2007 with a Penryn T9500 2.6 GHz Core 2 Duo, a Samsung EVO 860 and the BMC943602CS airport card. Under El Capitan everything works great, the old imac seems really fast but under High Sierra and Mojave (dosdude1.com) bluetooth is “not available” and the sound incl. keyboard volume control is messed up. There is a strange echo and artificial click in the overall sound, which is synchronous to the rythm of the music and which sounds like the speakers are broken or their membranes touch something on every beat. This is only on speakers, headphone sound is fine. And yes, I installed all of dosdude’s patches for the 7,1 platform. Any thought, ideas?