when mine came in from japan, the oil was too thin i was having a similar issue to you, with some help from nicely i got sorted :thumbs:Thanks this i will!
its common to be notchy then im assuming thought it was just my box but will have a go changing the gear oil and see if it helps, i was having problems with synchros crunching goin into 3rd in high revs in my old car (EK9) changed the oil and it cured it and i remember a local mechanic in bridgnorth saying "no it wont make a blind bit of difference if you change the gear oil" and it so obv did. :nod: