Ive noticed all my machines are hashing lower then spec for the past week or two. They are 1.5Gh/s 1.5Gh/s and 750Gh/s (one miner died). Not sure why the constant drop for so long. Temps, fans, pumps all appear normal

UPDATE: Lost power for a couple hours and when it returned the machines appear to be hashing and normal speeds, I guess a reboot helped them