I'm mostly encounter it with my 6800xt in my PC, because in rigs I've got 6-8 cards so share rate is higher, but it can be any videocard. Im mining flux at Herominiers and use big share size(24ksol) because overall it gives higher h\r, but sometimes when it's taking too long to find a share it would disconnect\reconnect from pool. I tried settings like 0 or 60 - and they work, with 0 you disconnect\reconnect after 10-15 seconds and then it starts doing it constantly. With 60 its like the same 10-15 second buffer + 60, but if I use like 999 or 9999 or something in between it seems it doesn't work because I get disconnect\reconnect sooner than it's supposed to. And I mean even with 999 seconds setting it shouldn't get any disconnects because single 6800xt finds a share sooner than that with 24ksol sharediff.