Be sure that the audio settings for the player match your home setup closely. If the player is connected directly to your TV with HDMI and no home theater is in use, set the digital output setting to PCM Stereo.
Check the DRC setting. Dynamic Rage Control will keep the sound at a consistent level. This can give you the impression of low audio especially with action films. Basically the parts of the film that should be really loud are made quieter to match the dialogue of a quieter scene of the film. If this appears to be the case, set this option to Off and play the disc again to see if the issue is improved.
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