Touch Font problem on ePUB from library/Overdrive

I bought a Kobo Touch last week and have managed to upload and view books via KOBO and a free ePUB book with no problem.

I then downloaded an ePUB from my local library (Oxfordshire) via Overdrive and Adobe Digital Editions. It uploaded fine but upon scrollling through the pages I noticed that most of the text was shown as:

ŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠŠ ŠŠ etc.

The odd paragraph was fine but most were illegible.

:help:Does anyone have any idea what the problem is? It is a setting I need to change or it it a problem with the original file from the library?

Thanks