Loss of hydraulics at high rpm

I have a 2003 BX2200 with LA211 loader. Bought used. All worked fine for 10hrs. Changed dirty hydraulic oil, filter and cleaned screen.

At low rpm >1200, hydraulics work fine. Run up rpms and all hydraulics move very very slow.
I cleaned the control valve and installed new orings.

If I disconnect the red quick connect on the loader and reconnect system works fine until I run up the rpms.

Any ideas as to why the loss of hydraulics at high rpm?

Thanks,

Dave

Hydraulic system was flushed when the oil was changed. Pump was not remove.

It seems to pump ok. Will lift full load without a problem. Just when rpms are up it seems to pressurise both sides of the system until you disconnect the loader red line and reconnect. Then it goes back to working fine until high rpms again.

Tractor has 1190 hrs on it

4/13/13
Replaced the QD on the FEL feed line. Problem solved. FEL now works fine.
Thanks everyone for the tips and advice