Volvo L90E powersteering pressure way down

Driving L90e today myself when all of a sudden the steering seemed a bit slow ,if it is not going back or forward it will hardly steer at all .The orbital unit seems to work as it should but when the steering load increases the steering wheel stops going round as if it is not getting sufficient pressure . I am just going to check the pressure now ,but was wondering has any one seen this before

Volvo L90E powersteering pressure way down