JD 410G hydraulic pump internal leak?

I have a 410G with a hydraulic bleed down problem. First of all there are no external hydraulic leaks I can see. I feel like hydraulic fluid is passing through a valve somewhere inside the pump.
I’ll lift the machine up with the stabilizers and bucket and after about 5 minutes of digging the tires will be back down on the ground and the machine will lose its stability because there is so little weight on the stabilizers. In addition to this the extendahoe will sag down about six inches in that same time frame. Everything sags at a slow rate. Can anyone help me figure this out? Thank you.

First a serial number would be needed.

Drifting issues will not be the hydraulic pump. Need some more details. Is it the front end coming back to the ground or is it the back end coming back to the ground? Is this something that just started happening? When you say "everything sags", do you mean every cylinder on the machine will drift? Do they drift with the engine running? Engine off? Pilot controls or manual sticks?

Thank you. T0410GX918534 is the serial number. Both the front end and back end come back to the ground. It hasn’t just started happening but it definitely has gotten worse in the past couple months. And yes every cylinder seems to sag/drift just a bit. Engine on or off. Controls are manual sticks.
After reading a bit I realize there is a control valve Between the pump and cylinder and that’s why you said it wouldn’t be the pump. Thank you for that. Another factor I’ll add is I only run hydraulic oil that is specified by John Deere to use in this machine. It has 2800 hours on it.

First thing I would do is remove the hydraulic filter and cut it open to see if there is any debris in there. With 2800 hrs and multiple cylinder's drifting sends up red flags for me. Post pictures of the filter media. Procedure for filter inspection at the link below.

How long have you had this machine, did the problem develop over a long period of time, have you had any component failures concerning the hydraulic system, if you bought it and it leaked down from the start that is troubling, A pump that failed somewhere in the units history could have loaded the system up with metallic debris and caused major damage, an inspection of a cylinder that leaks down badly is in order.