1Password 6 Windows Chrome Extension Sophos anti-virus blocking (Teams)

This is driving me crazy.

I have signed up to 1Password for Teams, and installed 1Password 6 on Windows.
I use Chrome, and have installed the relevant browser extension.

However, randomly, the extension will lose sync to the "Helper", and requires setting up again.
But it won't!
It keeps failing when I go to https://agilebits.com/browsers/welcome.html

So I have to disable our company Sophos Anti Virus service, and also the Sophos Web Filtering service, then get the Chrome extension to sync, which it does, then re-enable Sophos.

I have tried adding exceptions for the 1Password folder in Sophos. But this doesn't work.

I don't know what else to do and there doesn't appear to be any blocking logs from Sophos to suggest what is happening.

This is happening both in Windows Server 2012 R2 (terminal services) as well as my Windows 8 PC. Both have Sophos installed. My Mac which also runs Sophos is fine and works perfectly. So this is a Windows/Sophos/1Password 6 issue.

I never had an issue with 1Password 4 syncing using Dropbox on Windows Server 2012 R2/Windows 8. It always worked and never was blocked. So something has changed with 1Password 6.

1Password Version: 6.1.308d
Extension Version: 4.6.2.90
OS Version: Windows Server 2012 R2
Sync Type: Teams