USB OTG device limit?

[aranmjohn]

I have a 2012 nexus 7 tablet running a custom lollipop rom and kernel that supports usb otg and charging at the same time. The problem I'm running into is, it seems like using all my devices, ie digital audio converter, dvb-t for radio memory stick and charging at the same time is impossible. I have a cheap powered multi port usb 2.0,
7 port hub, and depending on the order i plug things in I can get two devices to work properly but never the third in any order... kinda pulling my hair out, should I try upgrading the usb hub to something more substantial? or is there something else I'm not aware of.

Thanks,
Aran