when u ask a question like that, please state...

.. what package and speed u r n?
.. do u mean ethernet or wifi or both?
.. r u usuing unifi stock router or yr own.. what model?
.. is "slow download/browsing for ALL yr devices or some?

becos there r 1000 reasons for "bad speed".

u need to give details for anyone to comment usefully to u.

ok... that is probably a local area unifi infra issue.

it is common... i get that every month or so... but usually for 1 hr only, then return to normal.

problems like these, my experience... best to:

.. talk to neighbors see if they have same issue.
.. report to unifi, see if they already know of a local problem.

boy... u may not believe it but i hv experienced x-files type problems, did not even suspect until a few miserable days later:

.. some contractor came to my road to install for neighbor... in the process, the idiot unplugged my port in the "green launcher", left it hanging there.

.. some gardener while cutting grass... severed the cable.

so, u see... believe it or not... shit happens.

nope fine from my end.

Did you try restarting modem and router? Tried on LAN as well?

wifi:-

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