intermittent dns issue

[Adrian4]

I was wondering if someone could help with what I assume is a DNS issue.

We have many sites in various countries. We keep our meraki configs fairly standardized. 

We also use Umbrella Roaming client on all laptops. Everyone uses the same basic policies.

At one small site, they are having intermittent issues connecting to Microsoft services, Power BI, SharePoint etc. The web loading screen will spin and spin until it says fails to connect. If the user just retries over and over, eventually it will connect.

The issue also seems to effect salesforce, but it does have a outlook integration.

The site uses the same DNS servers as every other site.

The issue is definitely site specific not device specific - if people from other sites visits, they will have the issue. As soon as they return to their regular office it goes away.

Its only a small site, 5 people usually but up to 15-20 when there are visitors. - They have plenty of spare bandwidth.

The issue seems to have started around the last week of July but we cant correlate any changes to that time.

Can anything think of something that could be causing this?

thanks!

[CptnCrnch]

I assume that the Guest visitors don't have the Umbrella Client installed? Do they have the same issues? Just to be able to narrow this one down a little...

[Adrian4]

yes they do, sry by guest i mean it isnt their usual office.

Everyone is a company employee, they all have the same umbrella install and use the same umbrella policy etc.

I have checked the umbrella logs, and they are definitely not being blocked. I didn't expect that either since the problem is only intermittent. 

They dont have any problems until they go this this problem site. They are fine at every other site except this one.