RBR20 and satellite issues - starting to get intermittent connectivity issues

Hi
I have a RBR20 router with two satellites and purchased last year. We have had good luck with our set-up but recently my desktop has been having connectivity issues....it runs off of one of the satellites.  Speed is also very poor as the (10 mbps) vs for example my phone (115mbps). I have been checking the speed recently on all devices and it is variable.

I also noted that the desktop is on 2.4 GHZ whereas other devices are on the 5 GHZ. How can I change this?

Also, could my issue simply be my wifi card?

Anyone have any thoughts/suggestions/solutions?