The speed tester seems to be slightly broken at times. Either giving completely inaccurate results or otherwise not functioning correctly. All you can do is persevere and it may eventually return the results you are looking for in the further diagnostics.
Thought as much. I wonder if the Mods could give some update/guidance regarding speedtester as I thought that flash was being phased out , or even why it throws out stuff about Tap 3 when minutes previously I got the correct further diagnostics.
It seems too hit and miss for a tool that is required for reporting speed issues.