CD-i member Seventyy Seven has a CD-i 910 player and the tray gets a little stuck when going back inside: This is a problem that occurs to more players. What is happening here? It's possibly a combination of two minor problems: It needs a little grease inside and it might need a new belt. The belt degrades over the years and by now, after 30 years, it is very well possible the belt is not as tight anymore and the wheel will slip over the belt. Retrostuff helps: "Use this part number for your search (or go for a regular kitchen rubber band).
CDM9 DRIVE BELT 4822 358 31168 (482235831168)
And don't forget to grease the rails and everything that has teeth on the disc tray.
Try greasing the tray first and while you're at it, look if the belt really needs to be replaced? This is what you will find inside (these are first generation players, like yours):
