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It seems unlikely that 1.22 has a problem as others would have spotted it by now, so I would suspect either the file has been corrupted and/or not installed properly, or there's another fault.
Did the upgrade appear to work ok?
Does the power-on screen confirm the new version has been installed?
If not, did you definitely unzip the download package correctly and copy just the firmware file DP-24_089.122 to the sd-card? You could try downloading the package again.
If this has no effect, what exactly are the CD fault symptoms? e.g.
Does the CD button work? Maybe it's just become intermittent, as other buttons sometimes do over time.
Have you tried another CD in the drive?
Either way, keep us posted.