OK - I was trying to investigate this and actually you cannot submit so many shares with this difficulty with 3 GPUs only. Conclusion is that stratum and p2pool difficulty implementation is different or p2pool accepts shares which it shouldn't (meaning you will submit many shares but will not find much blocks...).

Also there can be a valid question to miner dev - what is the definition of diff1 in miner for quark based coins

feeleep