Gear Change Problems 5th to 4th

Can anyone give me a bit of help please. Have just bought my first Land Rover which is a 1996, 300tdi pick up. Having a real problem when changing down from 5th to 4th. I see from other posts that it is not uncommon in what I think is an early R380 gearbox. All of the advice is that it is the baulk ring and the gear box needs changing however this is a 40k from new truck and everything else about the box is perfect, is there any easier fix than a complete rebuild or anything else I can try? Thanks All

sometimes you need to set springs 1 each side of gear stick turret under rubber gaiter 10mm spanner size bolt adjust spring pressure to align gear stick with 3rd 4th gear when stick let go from either side,change oil they never have enough oil changes ,can also be worn brg between mainshaft and input shaft

Taa for that, got it booked in locally with a LR specialist who is going to change the oil and try and adjust. He is quite confident but we will see!