SonyBMG is planning a subscription-based music download offering with a flat-rate monthly payment. CEO Rolf Schmidt-Holtz gave some extra detail to FAZ.net, after digital president Thomas Hesse first revealed his appetite for all-you-can-eat “access in a very free way with very little encumbrances” at Mobile World Congress in January: “The simplest option would be a flat rate under which a monthly payment would provide access to our entire music catalogue for all digital players, including Apple’s (NSDQ: AAPL) iPod.”

The plan would include some downloadable tracks as well as walled-garden plays (MP3s?), could let fans keep songs even after expiry and could cost six to eight euros a month. Sounds sketchy, and it’s not clear if this would simply license the label’s repertoire to third-party services and device makers as with Universal’s Total Music plan and EMI’s upcoming moves - but it sounds more like a brand new store is in the works. This would pose a number of challenges - a music store comprised of just one label is unlikely to succeed, and what is iTunes Store likely to think?

SonyBMG - in which Bertelsmann is considering selling its stake - appears to be talking with the other majors. Schmidt-Holtz: “The offer is more attractive, the bigger the music selection. I am not saying that it wouldn’t be interesting if we do it alone. But it would certainly not as exciting.

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