I got 4 moonlander 2's on a powered hub. On Win10 the moonlanders would eventually 1 by 1 show 0 for speed & restarting bfgminer didn't help. I'd have to power cycle the hub or remove each miner & plug them back in then they'd work for hours to a couple days.  I figured it could be a Win10 issue & was sick of dealing with restarting them so I bought a raspberry pi and now they still eventually go to 0 but i can just restart the bfgminer & they'll work again.  Granted I could just cron or script a restart but I'd prefer to get a real fix.  I'm testing the older initial release on the pi to see if it makes any difference because I noticed the latest says it had restart logic added which i figured there was a chance that was the issue.  Btw I'm running them stock (not specifying any speed on command line) and the hub claims to support 2A per port. It's the "Sipolar Well Work 20 Port Industrial USB 3.0 Hub Charger for iPhone/iPad/Cellphone with Box Shape Speed Up to 5Gbps " "Provides up to 5V, 2A (10 Watts) of power per port, for charging battery-intensive devices such as an iPad" so I didn't figure that was the issue.  It's actually a nifty hub in that it's like 2 hubs in 1.. The 20 ports are split into 2 sides, each with own USB type A port like a separate 10 port hub combined in 1 box.  In fact the other half of the hub is running 1 NEWPAC using an older pi without issues. Actually, before I bought the newpac I was running the 4 moonlanders on that pi with this hub with zero issues.. (unfortunately the moonlanders & newpac don't play nice together mining on same machine)  I was tempted to swap the 2 pi's around to see if the problem followed or not. For now i'm testing the initial release bfgminer with fingers crossed.
Thx
Bill