Invalidating CD-ROM cache

I would like to invalidate CD-ROM cache and to acomplish this task I’m
sending FSCTL_DISMOUNT_VOLUME to the device, for example \Device\CdRom0
(as Anton Kolomyeytsev said to me in this list some time ago). I’ve
experienced that, although the dismount command is processed without
error, the system doesn’t read CD-ROM again when, for example, you press
F5 in an Explorer view. I’m filtering all IRP’s sent to device cdrom and I
don’t see any new read request… it seems like if system was still using
information stored at the cache instead of launch again the process that
use to identify the media (reading sectors 0 and 16, reanding TOC and so
on).

Might anybody help me with this problem?

Thanks in advance…

Jose Vicente Sanchez Ortega.