Advice on fixing a Roland DP-8 plug-in half-damper pedal...

[MaliceX]

I've had this thing for just over a year now along with me EDIROL PCR-M80. Just recently I've noticed the pedal's seeming to have degraded over time.

For example, it seems to be making loud creaking/scraping noises when I press/depress the pedal, at the same I think the response ratio's gone down. (Like, I really need to put my foot down fully to have it read "127" and even the slightest raise would trigger the 0 switch. Of course this isn't noticeable when plugged in the EXPRESSION port, but on HOLD it's kind of something.)

What is the first thing to check if I open the pedal case?

Thanks.