Sometimes (and I haven't worked out when yet), the menu at the side appears in the wrong place, with the wrong colours, appears twice or maybe just as text. If I then do a refresh twice (using Firefox on my PC), the page refreshes correctly.
Here's an example of what it should look like: https://www.dropbox.com/s/u4iwvscsqy51y ... r.jpg?dl=0

And here's an example of what it looks like when it goes wrong: https://www.dropbox.com/s/kpas75pv0u9ls ... e.jpg?dl=0

Any ideas why this happens? It doesn't just happen to me - I had one of my testers report this too.
The site is www.pennine2020.penninescouts.org.uk
Alan
PS - I've posted the direct link to the images because sometimes I just see "image" where I would expect a picture.