Three ideas 
1) --suggest-diff 442
Using lower will be ignored on my pool
Or just set it on the Workers->Management page to 442
2) try: --gekko-compacf-freq 450 --gekko-start-freq 300 --gekko-mine2 --gekko-tune2 60
Of course, as obvious, make sure it has enough cooling
3) grab a screen shot so we can see what it says
1) --suggest-diff 442
Using lower will be ignored on my pool
Or just set it on the Workers->Management page to 442
2) try: --gekko-compacf-freq 450 --gekko-start-freq 300 --gekko-mine2 --gekko-tune2 60
Of course, as obvious, make sure it has enough cooling
3) grab a screen shot so we can see what it says
Wish me luck - after running over a week at 400 with no issues going to push it to 450 and see if the smoke stays inside the sticks