I'm going to try removing the plastic grill like you mentioned in another post to improve airflow and maybe if that helps out I'll try it out on Medium again.
I removed the plastic grill and reduced mine to low speed. I can barely tell it is running now and has been stable so I'm happy. If I were trying to ROI with it I would probably be disappointed, but using as a lottery miner I think it is still the best option available at the moment. I do with that they had a better way to order them but I got my unit and I think it's probably the only miner I've purchased with a credit card, so there's that...