per the reply from @tudor what is the make/model of your WAP?
It sounds like you're getting OK(ish) speed from the hub when you connect your PC over ethernet (i mean, i would expect better on a 200mbps connection, but the fact that you're getting >100 means that the connection is capable of those speeds...)
It's also reasonable to assume that the WAP is negotiating at least a 100mb connection to the hub (it should be gig, but doesn't really matter at this stage whether it is or isn't given that you're not currently limited by it).
So that leaves the WAP and/or the devices that are connecting to it. A year-old mobile phone.. i'd kinda expect that to be AC capable, but maybe it isn't..
is your WAP AC capable, and do you have any AC devices that you can test with?
if necessary, configure the WAP to broadcast different SSIDs for the 2.4 & 5ghz bands and force a connection onto the 5ghz to see if there's any difference..