@BIBURYBILL: I'd recommend checking out the sound options (Settings > Sound > Sound Mode) to optimise your listening experience. To change the sound mode, press the Select button. To make fine adjustments, press the up directional button, and then select Equaliser Setup, or go to Settings > Sound > Expert Settings to personalise the sound output. If your problem persists please go to Settings > Support > Self Diagnosis > Sound Test to see if this highlights any existing hardware issues.