Okay, after some further testing some weird stuff occurs.
One rig (3-560/1-580) hashes away just fine for nearly 1,000 submitted shares after 3.5 hours at just 1% rejection rate and around that time suddenly the rejection rate sky rockets with lots of "low difficulty shares" rejected and also "stale shares ... ignore it" that take the rejection rate above 10%. I basically just close and restart the miner and it likely will be fine again for the initial few hours.
On my other rig (1-560/5-580) it is working a bit better at also roughly 1% rejection rate, but then encountered inability to find mining pools and some disconnects/reconnects including a 3 minute span that resulted in over 30 rejected shares consecutively that caused the miner to restart.
Cannot figure out how to paste a picture so here is some text on the errors:
rejected(2449/22) diff 50.53M "Duplicate share"
waiting for a new job more than 60 seconds, disconnect
reconnect in 10 seconds
no active pools, stop mining
use pool pool.purkproject.com:7777
accepted(2456/22) diff 50.53M luck 123.67%
....
rejected(2456/23) diff 50.53M "Low difficulty share"
new job from pool.purkproject.com:7777 diff 85.90M
ADDENDUM APPLIED: 104175 --> 104176 7 blocks added
JSON invalid target:
rejected(2456/24) diff 85.90M "Low difficulty share"
rejected(2456/25) diff 85.90M "Low difficulty share"
rejected(2456/26) diff 85.90M "Low difficulty share"
rejected(2456/27) diff 85.90M "Low difficulty share"
rejected(2456/28) diff 85.90M "Low difficulty share"
rejected(2456/29) diff 85.90M "Low difficulty share"
rejected(2456/30) diff 85.90M "Low difficulty share"
rejected(2456/31) diff 85.90M "Low difficulty share"
This one is weird. Seems I need more testing with official Purk pool, and probably do something with gpu mixed rigs. Can you please try new version?