question about the pads. broken or tired?

Hey,

first time poster. i just bought a secondhand mpc1K. The unit has apparently been lying on shelf collecting dust for about 3 months.
The problem is this: The pads are not working for me, i have to
press them with all my might to get a sound from them.
The weird thing is this: After pressing one pad for about 10 minutes
it appeared that it slowly became more responsive. Its far from
the way its supposed to be, but its slightly better. Can this happen?
Can the pads lose their responsiveness by not being used for a while
or is it the (in)famous pad problem with the mc1ks?

Thanks,

Manolito