Sony has defended the £10 a month subscription fee it charges for complete access to Music Unlimited, the cloud based music service available on the PlayStation 3.

Music Unlimited, which launched late last year, features six million songs. The basic plan, which costs £3.99 a month, offers genre-specific and era-specific channels of non-stop music. The premium service adds on-demand access to all songs in the library and additional channels with new music for £9.99 a month.

Given the popularity of free music streaming software Spotify, which is funded by advertisements, some have complained that Music Unlimited is too expensive.

Sony, however, considers the subscription fee to be "fair", and told Eurogamer that those who complain do so because they are used to illegally downloading pirated music from the internet for nothing.

"The feedback is all over the place," Shawn Layden, executive vice president and CEO of Sony Network Entertainment, told Eurogamer. "Some people wrongly think music should be free. Why would I use this service when I can pull it all down Limewire for free? Well that's exactly what people ought not to be doing.

"We feel that way in the game business. We feel that way in the movie business. This is content. It has value. People spend their lives creating this, and so there has to be some way to reward them for their labour. It only seems fair."

Layden said Sony faces an uphill struggle in the battle to educate gamers on the value of content because piracy has been so widespread for so long.

"They have [got away with it] for years," he said. "We try to modify that behaviour. We try to get people to understand and realise that behind this music there are artists and those artists have careers and lives and a cost of living that goes with that.

"If you just lay out the value proposition, £9.99 a month for six million songs, any time, anywhere, all of the time, it's not hard to do the math on that. That's two trips to Starbucks to have all the music in the world.

"But users always want it to be less rather than want it to be more.

"This is a fairly established price point for this kind of offering in the market. We think it's equitable and fair."

Despite the price complaints, Layden said Music Unlimited has been "quite successful" – and it's most popular on PS3.

Why? Because PS3 owners are "programmed to receive".

"The PS3 user is, shall we say, more net savvy than others," he explained. "They're already into the network via the PlayStation Network, which has been up for about three-and-a-half years.

"They understand that world and what you get when you go there and how to navigate that.

"In the other areas where we're bringing the service across to consumer electronic devices, there is still some education to be done there to make people aware of that service opportunity.

"The PlayStation user expects new things to be coming through their network service all the time and so are programmed to receive, to see those things coming in and get associated with them."

Sony's aim with Music Unlimited, and other network services, is to make your PlayStation ID a ubiquitous sign-on for multiple devices, including the PS3, PSP, PSP2, Sony Bravia tellys and Android phones.