I don't think that's an Ocean issue, it is just the nature of ASICs, sometimes in 60 sec and S19 creates 175th on average and sometimes it only makes 45th, but on average (3hrs) it will end up near 100th.

Braiins does a 5 min hashrate which would be much smoother. But I prefer the 60 sec. Because I can tell quickly if my "full" hashrate is getting to the pool.