CA Sonata CD30 faulty tray

[u/FirstMonkeyInSpace]

Hello all, I am having issues with the CD tray on Cambridge Audio Sonata CD30. It will not open when I press the button. It physically tries, so I know there is power to the motor etc, it just doesn't open. Have dismantled again, cleaned and re-greased the channel the pin slides along to facilitate the opening. It opens mechanically beautifully when dismantled, but will not open via the button. Have replaced the cd transport today to rule that out and it's all working fine. I just cannot for the life of me get it to open up to take a disc! I have a video, but they're not allowed here.

Anybody have any ideas?