Spotify has 2.5 million paying subscribers

Spotify shifted from a largely ad-supported system to focusing on gaining paid subscriptions previously this year, limiting free users' listening time as it tried to push them to upgrade. It as well recently linked up with Facebook, requiring new users sign up via the social network.

While Spotify is winning over users, it last week lost 200 labels afterwards their distributor pulled out of several streaming services, citing "concerns that these services cannibalise the earnings of more traditional digital services".

"They provide poor revenue and have a detrimental affect on sales," STHoldings said. "Add to that, the feeling that their music loses its specialness by its exploitation as a low value/free commodity."