shifting problems

Hi, so I just got my first vw, I have a 2001 vw jetta tdi 1.9L, I was told it has a 2002 engine and a rebuilt tranny, it drove fine for the first 700 kms and now it pops out of 1st gear if you don't hold it in and sometimes out of 5th gear when decelerating with cruise on down a hill, I changed my transmission oil last night and adjusted the shifter cables but nothing changed, anyone know what's going on? Thanks!

Did you follow the method similar to what is described in this video?

https://www.youtube.com/watch?v=pUtZuLyr_sc

You may have to remove your shift tower and check the springs, bearing/seals and maybe for broken parts inside...ask me how I know!!!