The post on Plugable's 7-port charging hub power setup is from me
Possibly using Y-cables is contributing to the drop out?

I run 2x 2Pacs and 1 Compac on the Plugable 7-port 60w charging hub.
For form-factor and cooling I have a 2Pac on port-2, the other 2Pac on port-4, and the Compac on port-6. Nice and compact for cooling and each stick is on its own buck.

Tried running them without the y-cables, just plugged straight into the hub?