Reason? "Too many period films in Hindi - "1947-Earth", "Zubeida", "Lagaan", "The Legend Of Bhagat Singh", "Water", "Bose: The Forgotten Hero", "Kissna". I've worked hard on each of the themes, but the end result hasn't been worth it," Rahman told.
"The songs were either pushed into the background or not used at all, or worse still, used badly. Yeah, I feel very frustrated by this. But what can I do? Composing tunes is my job. How they are used isn't up to me."
Rahman seems unhappy with the way Subhash Ghai used his track "Hum hain iss pal yahan" in "Kisna".
"Though it was a love ballad, it wasn't sung by the lead pair at all. It was placed in the background. That killed the song's impact."
But the worst experience was "Bose: The Forgotten Hero".
"It's become 'Bose: The Forgotten Music'," jokes Rehman. "Sahara had promised a grand launch for the music and a grand premiere for the film. None of it happened. I had worked really hard on the music. But it all came to zero finally.
"After 'Zubeida' and 'Bose', I'm doing another film with Shyam Benegal. It's a full-on musical. But please, no more period films for now."
Having had his fill of a blast from the past, Rahman is now looking at a more contemporary kind of musicianship.
"All my Hindi assignments at the moment, including Rakesh Mehra's 'Rang De Basanti' and Abbas Tyrewala's romantic film are contemporary subjects. I'm quite done with period films now. I think 'Mangal Pandey' would be the last film of that ilk."
Rightfully proud of his compositions in the just-released "Mangal Pandey", Rahman reveals how he had been offered three films about freedom fighters, including Roland Joffe's "The Invaders".
"But I finally chose 'Mangal Pandey'. Yeah, the fact that Aamir Khan was in it did influence my decision. Aamir and I really jelled well during 'Lagaan'. In fact, I'm really proud of my work in 'Lagaan' and '1947-Earth', which also starred Aamir."
After "Earth", the third part of Deepa Mehta's trilogy "Water" is ready. It's the first project where Rahman has done the songs but not the background music.
"I moved away because of the controversies surrounding the film. What's the point of creating music for a project that makes some people unhappy? But I saw 'Water' recently. And it took my breath away."
Anything in Hindi music that Rahman has liked lately?
"Yeah I like M.M. Kreem's music. His 'Jadoo hai nasha hai' in 'Jism' was a surprise. And I like a couple of Pakistani songs that have been used in Hindi films like 'Murder' recently."