Poor speed and throughput via SpeedFusionCloud

I am using a Balance 305 with SpeedFusionCloud. I am experiencing very poor throughput when connected to SFC. Usually I am using 3x 4G LTE routers plugged into the WAN ports, + one USB 4G modem. Currently I have connected a residential fibre connection (100/20) to one of the WAN ports.

The application is to provide a bonded internet connection suitable for both VoIP (Zoom/Teams) calls AND video broadcast/streaming. I am aware that depending on the application FEC and WAN smoothing have different benefits, but in this case I require both at the same time.

With the fibre connected directly to my computer I get speeds via speedtest.net of 100/20. Connected to the Balance 305 and NOT connected to SFC I also see those speeds. However if I connect to SFC the speeds drop, usually to the reigon of 40/8. Even connecting the other WAN connections does not see the overall speed improve. I do appreciate that there is a bonding overhead but this seems way to restrictive.

I have a colleage with another Balance 305 and the same WAN setup and he is experiencing very similar results. It seems that the connection to SFC is the bottleneck here. In addition, depending on time of day and the exact SFC-SYD server we are connected to seems to result in different test results.

I would appreciate some pointers and advice on how to setup the connections and bonding - the bulk of the literature and information online seems to be directed to users with two units, one in a datacentre - we obviously don’t have that.

Apologies for the long post, please let me know what further information is needed to encourage thoughts and answers

Many thanks