Track lighting is great for lighting flexibility, but a flickering bulb in your track lighting is irritating. A flicker can be caused by several things, but it's most likely caused by a problem at the points of connection between the light and the track. There are several steps you can take to check and fix what is causing this unstable connection.
Make sure that the locking switch that secures the fixture into the track is all the way in and flipped. Jiggle the fixture slightly if the switch seems to be sticking, and make sure it is pushed all the way into the track. A fixture that is hanging loose and not locked all the way in place will not make proper contact and can cause flickering.
Check the track for build-up that may be causing interference if the above step is not the issue. Begin by turning off the power to your lights. Do this by switching it off from your circuit breaker box.
Remove the blinking fixture, as well as all others. Check the inside part of the track for dust or gunk. Use a paintbrush to remove debris and thoroughly clean the track with a damp sponge or rag. A bit of degreaser can also be used. Track lighting in kitchens frequently needs to be cleaned of grease.
Check the contact prongs of the fixture. Wipe them down with a damp sponge or rag if they are dirty.
Make sure the prongs are not bent, as this can also cause flickering. Make sure the prongs are sticking high enough up to make contact with the track. Try to bend a bent prong back in place with a screwdriver to create an even contact, or if the prongs are too badly damaged or broken, replace the fixture itself.
Ensure that the track is correctly inserted through the transformer, if the entire track is causing blinking, not just one fixture. Check the connection between tracks if you have more than one linked together. Try replacing the track if everything else seems fine.