I have a Bitfury BF3500 and recently there was a power outage. After the power outage I turned the miner back on and it was not connecting to the pool despite the fact that the internet was up and the power was fine. A few hours after, I noticed that it was mining, but at a much lower hashrate-like from 3 Th/s to 4 Gh/s. I noticed this drop in hashrate from looking at the pool page (I mine with cex.io), but when I checked my miner it said that it was mining at it's usual hashrate which is about 3 Th/s. Somebody told me earlier that this sounded like an issue with low difficulty, although I'm not quite sure what this means or how to fix this.
Here is a screenshot of my stat page:
http://imgur.com/R9Nq3zE
