Hi Paul

Thanks for the reply, and apologies for the delay replying, I'm just back from a holiday.

Whilst I have no doubt that in theory what you say is correct, I've just borrowed a Windows 7 machine from our IT department as I wanted to check if the users were doing something wrong, but I can confirm that the image quality is definitely degraded compared to the Windows 10 machines. I tested it using the same document with the same image - I can send the output from both machines if you're interested in seeing it. I don't think it's the code though, possibly something to do with an older version of Word reducing image quality to save space maybe?

Thanks
Andy