I have the m250 and just tested it. You can 'access' the euqlaizer while in FM mode, but it did not seme as if it had an imapct to the music when I was asjusting the settings etc.
so whatever signal comes in for FM, it does not seem I think, that the equalizer impacts it. Obviously unlike when you are listing to the MP3 files etc
Does the equalizer operate when the Sansa m230 is in FM radio mode?

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