With Gminer mining Grin 31 I have from 10 to 15% rejected on f2pool. Bminer gives 0-0,1% rejected. Are you going to come up with it?
Is the ping displayed in the miners the same or different? The fact is that in different miners I have different pings to the same server.
Same issue here. 10% reject on pool, but doesnt show as rejected on miner. G31 on f2pool
Perhaps this is the problem of the f2pool pool itself, there is no such problem on other pools, even where the ping exceeds 200 ms. Maybe the developer will respond.