I finally got my 2 S9's running in  a ducted enclosure and after running for 24 hours I keep seeing Lstime's that sometimes run up to 20 minutes. I pinged bitmain on all of my miners and they show 15-25 ms. My concern was that I have the S9's hooked up to an old 10/100 network switch and the 2 D3's hooked to the 10/100/1000 router. As I haven't had time to try different configs(switch network wire/change to a different pool), I wanted to see if I should even worry. The pool hash rate is a zigzag line as the Lstime creaps up and finally starts over.