Quote from: phase2 on October 25, 2017, 11:38:57 AM

After Byzantium update block times are shorter now. If your gfx card is computing a share from a block which was already found, its a stale share. Stale shares are a bit higher for everyone now but mine are still around %3 on ethermine. If you have low hashing power i suggest you mining on a less crowded pool.

I think this is indeed the issue as I mine on ethermine and only have a few % total stales, but I have a fair amount of miners pointed there. If I look at an individual miner's stats they can range anywhere from 0% stales up to 8%, but the average of all my miners is only 3%.

So while the shorter block times are causing more stales in general, I think it is just more noticeable for smaller hashrate users than it is for larger miners. It's probably just normal variance and you don't notice it when the stale rates are lower, but when you see a 8 or 10% in the stales column you think suddenly something is wrong. Check back in a few hours and I suspect it will have dropped again.