RX570 hashrate changes on its own

#1

This is kind of weird. One of my cards is a RX570 XFX 8gb. Mining ETH on Nanopool, getting about 30.6 mhs. After mining at this speed for almost 12 hours, I look this morning and its showing 37.5 mhs. Its done this twice out of the blue. I am not using AMDtweak on this card either. It is bios modded and has dual bios. It was throwing a few incorrect shares prior to increasing its hashrate but it was only like 10 in 12 hours. Any ideas whats going on?