JCB 8015 joystick issue.

[Pluckacre]

On this 8015 when operating any hyd service it works slow until another service is activated then works at normal speed, so if you crowd the bucket it's slow until you boom in or slew ,and vica versa.
Any ideas, electrical or a valve fault ??
Thanks in advance.

[Muz]

On this 8015 when operating any hyd service it works slow until another service is activated then works at normal speed, so if you crowd the bucket it's slow until you boom in or slew ,and vica versa.
Any ideas, electrical or a valve fault ??
Thanks in advance.

check there isnt some obstruction making the breaker pedal stuck on (if it has one)