Slow Office 365 Outlook only a few MB's throughput

Hi all,

I cant explain why by example Outlook 365 is such as slow, we got on day with about 80-100 online machines, only peaks of 2 MB/s, and outlook is very slow at all workplaces especially on which more than 1 mailbox is integrated.

directly connected, without UTM in between, to the fibre internet connection its a lot faster.

Are we throttled by Microsoft Online because we are a little enviroment for them?

Or got anybody else this behavior too with using Microsoft Exchange Online?

it was slow without and with webfilter using, so there is not the problem either.

We got 2 SG230 which are not at limits having cpu and RAM like 50-60% under stress

Hopy anybody has any Idea what I can try too,

thanks in advance!

best regards from germany

Danny