Why is the button for cassette pushed in and not coming out?

I am working on a similar problem for a similar unit which includes turntable, cassette player, CD player and radio. The unit was manufactured by EMI Global Inc. and is a model CSL9. In this case a cassette is still stuck in the tape player, and the eject button will not pop out. I have not been able to find any service literature for the unit, so I am guessing the player is no longer made. But I may try a recovery repair on the tape player anyway. If I discover anything that may be of help to you, I will let you know. I have not noticed any change in the quality of playback with LPs on the unit. I would be interested in knowing more about how the sound of yours changed.