How to temporarily disable VirtualHere Server on Synology NAS

I am running a licensed VirtualHere Server on a Synology DS918+ NAS.

I am currently having a problem with really slow write rate to an external USB HDD (using Synology USB Copy to copy from the NAS internal drives to the external USB HDD). It is probably a Synology issue rather than a VirtualHere issue, but to confirm that VirtualHere has nothing to do with the problem I need to temporarily disable or uninstall VirtualHere. The Synology GUI for VirtualHere provides no help - it is basically just a page with a link to the VirtualHere site.

How do I temporarily disable or uninstall the VirtualHere Server on a Synology DS918+ NAS?

Thanks