OK. The noises, I am unsure of.

Three causes of the pedals trying to turn on over run in third gear are:

• Too tightly adjusted cones.
  
• No lubricant and or corrosion
  
• Wrong lubricant

Use of the wrong lubricant - specifically, too heavy a grade of oil or the wrong grease. The SRF3 and the AW too require a very light grade of lubricant on the internal parts, except for the main ball races at either side which use pretty ordinary bearing grease.

So far, you've eliminated the cone bearing adjustment, broken parts and obvious severe wear,and unless you've filled it up with the wrong lube that leaves a lack of lubricant.

Dry planet pinions might make noises, but then they would be making a noise in other gears too because they rotate all the time. Of course dry and corroded pawls and dogs on the top gear set up might cause harsh noise which wasn't present in the other gears. A dry hub can make horrible noises. I recenty bought a 39 year old R20 and the hub sounded dreadful when I pedalled backwards or spun up the wheel and then stopped pedalling. I put in a good amount of 3 in 1 oil and it was cured in minutes.

If you've looked for broken parts and found none, I'd come down on a dry hub. You can trickle some light oil into the hollow axle while the bike is lying on its side or squirt it in with an oil can. If you've tried everything else, squirt some in - about three tea spoons full. If you put in too much, it will just come out and mess up the wheel. this is easily cured by washing it down. with a squirt of that citrus bathroom kitchen cleaner. This is a tremendous degreaser when used neat.

My hub has run purely on light oil for 2500 miles and is totally good, even though it is a grease type hub as all the SRF3 ones are. You just have to keep on with adding a few drops of the oil every month or so once you start on that game.

Let us know how you get on. I am really fascinated by these hubs.