What went wrong between Sonu Nigam and Zee's honcho?

Bollywood has been talking about the repercussions of a showdown that happened between Sonu Nigam and Subhash Chandra Goel, head honcho of Zee, a few months ago. The buzz is that Zee Music Company has imposed a carpet ban on the singer and that it is also looking to dub the songs he has sung for films which Zee will release.
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So, what went wrong? A source says, "At the party hosted by Amar Singh, Subhash had said Sonu was his creation and he must get credit. Sonu responded saying he always acknowledges his roots.There was a slight commotion and Subhash lost his cool. Finally, Amar had to intervene and sort things out."
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