Noise and incorrect preheat temps

I’ve been getting noise and an inability to have the R1 charge to the requested 180C. It seems to like 145 or somewhere around there. Any suggestions? Is the issue the latest firmware (Running 512)? Can I back down to a more stable one? Also, note that the induction fan cycles to various speeds (somewhat rapidly) before it is even close to the preheat temp requested; this is relatively new and wasn’t the case when I bought the Bullet V1. I’ve been feeling that my machine is wacked since the last couple of firmware upgrades. I am an original V1, IR sensor. I should mention, the sensor had been cleaned prior to this run and was clean even though I cleaned it yet again. One community respondent thought I might have a defective BT probe.

Any help is appreciated.