Having browsed the user manual I wonder if you plugged in the Sony BDV T57 Home Theatre System while the Polaroid FLM-2632 tv was powered down via the optical cable .
Then powered up the Sony BDV T57 Home Theatre System first and then powered up the Polaroid FLM-2632 tv
Maybe the Polaroid FLM-2632 TV has to detect that the Sony BDV T57 Home Theatre System is connected and powered up when the Polaroid FLM-2632 powers up. To activate its digital audio out ????
The note part about only being available only under HDTV (cable/air) mode. Might be the cause of your hassle also ?
DIRECTLY FROM THE USER MANUAL
? Connecting to Audio Receiver:
Use an audio cable to connect the audio receiver's audio LINE IN jacks to LCD TV's
AUDIO OUT jacks. ? Connecting to Digital 5.1 Sound System:
Use an optical cable to connect the audio amplifier's OPTICAL IN jacks to LCD TV's
OPTICAL OUT jacks.
Use a coaxial cable to connect the audio amplifier's COAXIAL IN jacks to LCD TV's
COAXIAL OUT jacks.
Note: Above mentioned function is only available under HDTV (cable/air) mode.
? Connect all AC power sources, before turning on the power switch of the LCD TV or
other connected equipment.
? Press the button on the remote to turn on the LCD TV."