Suddenly it was like this during use, but the network is no problem in other applications, but it can no longer be connected in XD, and XD cannot be shut down normally. You can only use the task manager to force it to shut down.
It's happening across any file I open. Albeit most of our files are of similar complexity and size - generally 2 to 6 artboards, each containing a web design. This doesn't seem excessive, and has never previously been an issue;
It's vitally important that this is resolved as swiftly as possible. At present XD is literally unworkable - I click on a page element and the application freezes for around 30 seconds. And other applications become unresponsive as XD is constantly pushing the CPU to 100%.