CDs play fine on my CD player.
This will seem strange, but because I HAD to burn a CD, I got the tracks in question onto my hard drive via the Sony CD-RW and Sony's Sonic Stage software (as MP3 files). Nero then burnt a playable standard CD of them. Obviously I'd prefer not to have to go through that palaver every time!
Have just tried again with a CD which plays fine. Nero appears to "add" the tracks to the "my audio CD" window, but when I press "play" on the same window it comes out as clicks like the CD did.