Splitting Tracks Audio Issue

Hello all

I am using Cubase 5 and have been recording fine … bought Kontakt and use various instruments … here’s my issue:

Record a Strummed Acoustic guitar part , works okay

Split the track so that I can copy and paste required parts and delete mistakes/dead space

On playback the first bar of the remaining part is muted, also if I move the part the playback sound is out of sync

Please can you help, much appreciated.