Mid 2015 Mbp wifi issue by location I have a mid 2015 Macbook Pro.

When at home, WiFi is as good as can be expected, approx 30-40mb down.

I stay away from home at another house during the week and whilst all of my other devices achieve good WiFi (phone, tablet, firestick) my MBP almost grinds to a halt.

Whilst at that location I set up my phone as a hotspot and connected the MBP and that worked as it should, all fine, approx 10mb down. When I then switched back to the in-house WiFi however, it was back to an almost non-existent crawl.

I'm not big on networking issues so not sure where to look for any clues as to what could cause this.

Are there any tests I could run which would allow me to narrow down what the problem is?

EDIT

Ok, really weird behaviour now...

I decided to strip back and not have anything attached to my MBP and run the test again (using speedtest.net). Approx 70mb down. Wtf! Then as I add things back on, one by one, power supply, external monitor (video, not audio), keyboard (usb, music), headphones, usb hub (DAW dongle and external drive) it degrades with each addition, approx 10mb each (including headphones which are passive surely).

Has anyone seen anything like this before?
This is not the perfect answer, but it is an answer...

Move everything away from your MBP that's plugged in to it.

When in location A my set up is different to a more cramped set up B.

My MBP was sat underneath a 43 inch ultra-widescreen monitor, with a usb 3.0 hub containing, amongst other things, my external drive, sat atop it. As soon as I separated them all as far away from each other as possible the speed went back up. Not back up to anything like it was with nothing attached, but acceptable.

Hopefully might help someone in the future. No idea why it's even an issue, I'm guessing everything emits something that clashes (potentially) with something else.