What is causing the loud popping, cracking noise? - its not the ptfe banging on the right side of the cabinet as the toolhead is furthest to the left front corner, and its not the Z belts slipping as the bed is not moving. Is there a fix to this?
Cracking in the front right corner?
If yes, then check the 4 screws (2 left + 2 right) on the back of the printer. In my case 2 of 4 screws were not tight
I hope this will fix your problem
Check out this video 
Hi Steve,
Thanks for your reply, from looking at printer face on (door in front of you), its the front left corner. I cant see if there is anything in the way or catching on the belt. It has been suggested it may be the feeder gear slipping, but this only happens when the toolhead is at the front left corner which makes me think the ptfe is being strained, so im going to print a ptfe strain support and see if that resolves the issue. 
It’s the plastic cover protecting the PCB for the control board.