Cuff joined Flextech as commercial director in 2000 from Initiative Media. He moved into his current role last year.
He leaves the company at the end of the month and will be on gardening leave until February 2004. Cuff insists there is nothing strange about his decision to leave, saying it was time for a change.
"I've really enjoyed my time at Flextech. It's now a strong player in the broadcast industry. Looking forward, I didn't feel there were as many big and exciting challenges as I might find at other companies, and I feel the need to make a change," he said.
"It's a very exciting time in the broadcast media and advertising world. I've got experience of different aspects of the marketplace and crucially how to connect commercial and creative. I'm excited about a new challenge in a new environment."
At Flextech, Cuff is credited with setting up long-term carriage deals with NTL and BSkyB, a new advertising strategy and implementing cultural changes at the company, which has shrunk from 450 staff to 300.
Cuff joined Flextech following its merger with Telewest in 2000, which valued the content firm at £2bn.
At Initiative, he worked in a number posts including group manager and broadcast manager before being appointed to the board and to the post of broadcast director in 1994.
Flextech's TV portfolio includes wholly owned channels Bravo, LivingTV, Trouble and Challenge?. Flextech is also BBC Worldwide's partner in the joint venture UKTV, which includes UK Gold, UK Gold 2, UK Style, UK Horizons and UK Drama.
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