I am finding this strange. I was on 3g on a fairly new iPhone 6s, on VIRGIN. I connected to the WiFi 5g in my apple settings as normal. The tick is there, but very intermittent. I rang Virgin up as everything in the home is Virgin, they stated it could be because i have a 3g sim and not 4 g. Virgin sent me a 4g sim and set up as usual 5g in my WiFi settings. My modem is super hub 2.
Even though my main mini mac is in the room and i am even next to it, it wont work, or extremely snail pace, so having to take it off WiFi, and use 4g. I have turned phone on and off and still intermittent. Works fine on 4g. My iPad also has problems, but that switches itself from 5g to 2g and back again whichever is the better signal.
I don't appear to have issues outside of the home eg, work, friends houses etc.
Even as i type this, on my main mini mac, in the corner of the monitor, the WiFi signal (half moon shape) is flickering up and down, although turning pages.
I have done everything as much as i know, thank you.
Did you manage to try a few different wireless channel yet? Before we can continue to investigate we need to ensure that every opportunity to improve the wireless performance, has been explored, you might need to try a few before you find the one that is best for your environment.
Hope to hear back from you soon,
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