What do you think about this slide movement?

[RKassl]

Recently I noticed that the kitchen slide is not extending at the same speed as it used to. When I extend the slides the order of movement is the kitchen, the entertainment, they finally the large dining slider. For some reason the kitchen slide is moving very slow, once this is out the other two move normally. On retraction the sequence is the same but the kitchen slide retracts the same way as when new. To troubleshoot, I shut off the two other hydraulic slides and just moved the kitchen slide, absolutely no sluggish movement, it extended and retracted like it should. What do you think I am seeing when I let them all out in the normal order and the kitchen drags? I am plugged in on shore power, and battery is fully charged.