Pel Job 1.5 min digger - slow servos

[Yozza]

Ay up folks,

My builder has a Pel Job mini digger but he as issues with the the hydraulics served by the the servo controls. The blade and tracks respond as soon as the digger starts, but the servo controls take a minute or so before they move the dipper, boom, bucket.

Any ideas where the problem may lie? Where should I start to look first?

Thanks,
Y