Imported audio files: master/compressor/filter behind?


I have recorded a bunch of tracks using an external recorder (Zoom H4N) and imported them to Cubase. Although the sound I hear when I load the tracks in Cubase is completely diferent from what I hear when I open the files in my laptop using a simple music player or when I listen them in the recorder. I have no equalizer or inserted effects in the audio track, so my question is - Is there any compressor / limiter / master file behind? If so, how can I remove it or mute it?

Thanks for the help (again!)