Can't get CD drive recognised

[Astral]

I'm setting up a 4g CF drive + CD slim drive in my 1200. No probs getting CF formatted and booting when it's the only thing connected to the IDE cable - and gees it's fast! But, as soon as I connect the CD drive, neither the CF or CD drive is recognised. I've tried connecting each device on different fittings on the cable. The only jumper to change master/slave settings is on the CF card - which I've tried all combinations of - master/slave, slave/master, and no jumper at all. There is no master/slave jumper that I can see on the CD drive, and I think that's where the problem lies - not being able to set them means the master/slave settings are clashing. Has anyone come across this and knows how to sort it out? Can I just cut a particular wire on the cable, or bridge some pins or similar?

[Astral]

There should be a way without resorting to buying another adaptor. A normal sized drive is recognised fine, but that has a master/slave jumper on it - which my slim one doesn't. I have confidence once the settings can be set properly all will be ok - that's what I'm thinking...

I've tried resetting to test for slow drives, accelerator and so on - no difference.

I think this "All newer IDE/EIDE hard drives can be jumpered as Cable Select (CS or CSEL). This is an alternate way to indicate which drive is master and which drive is slave (instead of jumpering one drive as master and one drive as slave). Cable Select jumpering requires a special IDE cable with wire 28 not connected to one of the drive connectors, which would configure the drive attached to that connector as the slave drive." might be part of the solution.