AFM onVUE issues

Hi everyone, I had my ACCA AFM exam today via OnVUE, and everything was going fine until I opened the Word and Excel windows — there was a huge input lag. I was typing, but the text appeared on screen with a noticeable delay. The proctor restarted the exam multiple times, and I even rebooted my PC, but the issue persisted.

What’s strange is that I’ve already passed 9 exams using the same setup (same room, laptop, however this time I used an external monitor + keyboard, but same Wi-Fi), and never had any issues. I’ve now rebooked the exam for June 11, but I’m worried it’ll happen again.

The OnVUE system check passed, but it doesn’t let you test Word/Excel performance, so I couldn’t detect the lag in advance. Has anyone experienced something similar? Any idea what might cause it — or how to avoid it next time?

Thanks in advance.