XDJ RX2 Version 1.20

I just bought a XDJ RX2 that comes with the 1.20 version. I had the following issues playing with it stand alone (not with computer connected):

1. on 4 times the sync didnt work at all, the beatgrid seems to move forward constantly, even turning off sync it was impossible to mix, since the two tracks did not stick together, since the beatgrid seems to move. 

2. Using the slip loop mode on several occasions, when released, it came off beat (using sync) 

Are this issues solved with further upgrades?

Which upgrade do you recommend?