My Toshiba DVD player is connected to the TV using the HDMI interface and also to my 5.1 sound system using an optical connector. My DVD player is set-up to send "raw" 5.1 sound out. It works fine with my audio system, but when playing some 5.1 DVDs, the message box "incompatible audio signal detected" pops up repeatedly, obscuring the center of the picture. (It would not be so bad if it displayed at the bottom or sides of the screen). Both the sound and the picture work fine, except for the message box popping up. Does anyone know how to suppress this message?
My TV is set-up to output audio to a 5.1 sound system and is connected to my 5.1 sound system using another optical connector and works fine with broadcast HDTV "surround" signals, detected as 5.1 by my sound system.

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