This tactile switch is among other things used for play and cue on Denon DJ. The two pin switch looks almost like the play and cue switch used in most Pioneer Dj units (DSG1117) however these two parts can not replace each other due to a difference in the heights of the switches.
Replace this part if your button does not respond or only works periodically. The part needs to be replaced by soldering.
Part number
Denon DJ – Switch Tact 5mm 160g Horizonta
DN-SWEVQ11L05R