Isobuster shows 'No media present' which I suppose is to be expected since that is what everything else shows, it is just ignored. So much for the comments I have seen elsewhere about CD drives treating these discs as normal CDs if HDCD is not supported. Presumably this format (seem to have blinked at some point in the past and missed this) has died/is dying and is no longer supported. I knew about SACD but not this, but probably just lucky with all the CDs I've bought.
The drive is an HP DVD A DH16AAL SATA CDRom with Lightscribe but not HDCD it seems. My Hi-Fi is quite old so fortunately it plays on that and presumably I'll be able to rip using Audacity (24 bit or probably 16 bit) but I'll be more careful about buying Cds in future. Don't think it's worth seeking a new drive just for one CD!
If anyone knows of a utility to check the capabilities of CD drives then I'd be grateful and I might have missed some setting as the soundcard is certainly capable of playing these discs. Thanks all.