First thing I'd try is to tighten the fitting if possible. But if it's whining I'd say you will be buying a new pump anyways. maybe you can flush the fluid and the noise will stop, maybe the fluid has just absorbed too much water/dirt.
That would mean that the pump is sucking in air and fluid. That will make it whine for sure. If the line isn't cracked just try a hose clamp, pull the top hose and bleed the system by keeping the reservoir full with the car idling and the air should work it's way out. Hopefully that's all it is.
If the line is damaged you may be able to cut a bit and splice in a good section, but I'm not sure on that one.