Lot's of pools under DDoS rolling attack it seems.

 It depends where you are looking to see your hashrate. If it is the estimate from the account page - that is affected by the last 10 rounds, for all workers together, or based on shares in current round for each worker. If you join a round already in progress, that will be a poor estimate. If your hashrate on your actual device as seen from miner output, well now that would be weird!
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