Ok so I thought I would give an update.
I have sanded the base of the nut with 180 and it has made a slight difference however doing open chords is very difficult. Especially an open C major chord. The string height at the nut is way too high.
I have spent hours reading and watching video's online which has given me a slightly better understanding to adjust the buzzing on the frets, setting bridge height, action and intonation.
From my research I think I really need to adjust each individual string height in the nut.
Should I purchase some quality nut files(or just use an old guitar string) and a bone nut because they are more durable?
Cheers,
Alkay.