Hello + my audio problem

Hello, my name is Keith Power, I’m an oldie in years but pretty young computerwise. I hail from Toowoomba in NE area of Australia. my retirement hobby is Photography (mainly insects - No model fees :slight_smile: ) Eventually i hope to generate DVD slideshows.
Currently I have a problem after installing an OEM version of Nero 6 burner software hence my showing up here!

Prior to installing Nero, “Win Media Player” functioned normally, immediately after installing Nero the audio on a DVD movie is dead, however audio CDs still play normally - I did a search but found nothing to match this problem and I am at a complete loss. Would appreciate any suggestions… TIA Keith