Tigger when user drags seekbar

I have a button that changes to state 'disabled' when the end of the timeline on the slide is reached.

When the user drags the seekbar, lets say back to the middle, to re-listen to part of the slide, then this button stays disabled.

I am trying different ways that the button becomes active again but so far I have not found a way. Unfortunately there seems to be no option to use the dragging of the seekbar as a trigger.

Anyone has an idea? Thanks :)