Paper cassette selection when using Auto-Select

[cmkessell]

Does anyone know what logic Canon printers use when deciding which paper cassette to use when Auto-Select is enabled?

I have a MB5350 printer with two cassettes, both set to A4 paper.  When I first bought it it would default to cassette 1, as expected, but it's recently decided to use cassette 2 instead.  This unpredictability is irritating because we keep "good" paper in one cassette and cheap paper in the other.

Is there a setting somewhere to make the printer prioritise one cassette over the other?

[merrymary247]

Are you using Windows or Mac? You can select your paper source from the print preferences dialog box, but the location varies on OS.

[cmkessell]

I'm using Windows 7.  I know I can use the Windows printer settings to force the printer to use cassette 1 or 2 but I'm just curious to know what logic the printer applies when auto-select is used.