The reason it is being said that Arjun didn't like Farhan hogging all the limelight post the film's release.
Apparently, buzz was also that despite having done a better job as an actor than Farhan in Rock On, Farhan managed more accolades since he was also the producer of the film and a media favourite. But it seems all these were nothing but idle mind planted gossip stories of a few tabloids.
Arjun has clearly stated that all these rumours are nothing but crap and has further added that he has got enough credit and accolades for Rock On and so has Farhan. Arjun feels Farhan deserved it and that having worked with him as a director in Don he has a lot of respect for him.
Arjun had earlier ventured into production with I See You but now it is learnt that he is going slow for his second production since he wants to concentrate more on his acting career.