Hi, it looks like the same issue that's occurring on Weiweiweiwear's Mac. A plausible explanation is that it's related to the feedback the Teensy sends to the USB host:
This would explain why the problem doesn't occur on all Macs—it depends on...
Hi, some people succefully tested the multichannel usb audio class with Mac. On the other hand we know at least of one case at which it didn't work. So I guess you just need to try it.
You would need Teensyduino 1.59. Then you can follow these...