Since day one my iMac Pro has had weird sound glitches where the sound breaks down as if it was recorded on too high volume (the volume level doesn't change), basically the sound is like it is going through distortion filter in a same sense you could compare the sound of acoustic guitar to distorted electric guitar. It doesn't matter if it is external speakers or the internal, it happens the same. It will stay like this until change from external output to internal or vice versa depending which one you had on when the problem occurred and I remember few times you had to switch it back and forth few times before the problem went away. After upgrading OSX the phenomenon became rarer and while it sometimes still breaks (and stays broken until the output switch), now I hear loud "cracks" popping every now and then but the sound returns to normal after that. The "cracking" sound is bit like if someone moved the audio jack in and out when the speakers are on. Since the error appears on both internal and external speakers I think we can rule out faulty cable or even faulty connector on computer. This has to be some sort of sound chip or software problem. Has anyone else run into this? If yes how did you solve? I can't reproduce the error and sometimes it happens often, sometimes it can take long time for it to happen again.