We have two Apple computers next to each other on one desk: a Mac Mini and a 27” iMac (both late 2012) and both running macOS Sierra 10.12.3.
We have a Wi-Fi router in the next room (about 9 metres away from furthest machine). It's a Virgin Super Hub 2ac.
The iMac connects on 5G and works well – it rarely drops out and is quite fast (DL 49.37 Mb/S).
The Mac Mini connects on 2G (will not connect on 5G – it almost immediately defaults to 2G). It is often (but not always) painfully slow in connecting to websites (particularly in the evening). It makes it almost impossible to use. DL speed this morning was 18.96Mb/s.
This is very frustrating. I have spoken several times to both Apple and Virgin. Both have seemed helpful at the time. Virgin have adjusted some settings remotely which seemed to work initially but problem returned. Virgin claims the Mac Mini is not able to pick up the 5g signal because of its specification.
Is this true? Do we have to buy a new computer to replace the Mini?