issues setting up 2 USB headset/mic with Macbook Pro.

Hello. I'm having difficulty getting my MacBook Pro 2015 to allow a second headset through an aggregate device. I have set the aggregate device up through Audio/midi setup, and selected the headsets, including checking the drift option.. When I move to the sound preferences, and select the aggregate as the output and input, I get sound from only 1 headset. I am using a Logitech headset and a G-force gaming headset connected to the Mac with a USB hub. I am running the latest version of High Sierra. I am looking to use both mics/headsets for live broadcasting with NiceCast and to record for content creation. Help in understanding what might be the problem, or even another solution which does not require purchasing anything more than I already have would be greatly appreciated
Thanks