First request for help!! (please!)

Hey there, I have a defender 90 R reg, had her for a couple of months and attempted a few small bits and pieces to get her back to glory. Just got back from Exmoor and whilst there noticed a gradual squeaking noise from the front....noise starts whilst power is on (not when coasting or not in gear) and gets quicker as the wheels turn quicker so anticipate something wheel based (duh)? When looking at the rear of the wheel where there is a swivel type ball there is an amount of grease/lubricant on the plate. I have tried to take a pic but it has not uploaded. Anyone able to point in the right direction, is this likely the cause of the noise?

check brake pads and pistons ie not seized,and wheel bearings, if it was cv youd expect it to be worse in full lock , though its worth putting half a sachet of one shot in swivel if its shown signs of leaking out , though eventually you may wish to change seal and swivel housing if its pitted

I had something similar which turned out to be caused the friction material on the brake pads separating from the metal backing. A couple of packs of Mintex's finest cured it, so was a quick and easy repair.