Mixdown session using Multitrack Editor and Effects Rack causes artifacts in mixdown file.

I have several tracks playing in the Multitrack Editor with an Effects Rack comprising of EQ, Dynamics Processing, Auto-Tune, and Convolution Reverb.

Playback as is appears to be fine.

However, when trying choosing Mixdown Session To New File (Selected Clips) or Bounce To New Track will create a few artifacts in the new mixdown file.

If I turn off the Effects Rack and do the mixdown, there are no artifacts. I tried clicking the Pre-render Track and it's the same option.

The work around is to not use the Effects Rack but process each track with the desired effects permanently and then create the mixdown file again.

Anyone know why this is happening? Is there a way to fix this bug so I can still Mixdown session with the Effects Rack in use?