Try going to ¨Options¨ > ¨Playback¨ and use these tools:
Volume Auto-Adjust (Range Compression)
Dynamic range compression amplifies quiet passages in the audio without making loud passages any louder. The Weak setting applies the least amplification and sounds more like the original recording, while the Strong setting applies the most amplification.
Clarity low frequency cutoff method (Low Frequency Cut Filter)
Express Scribe uses a Low Frequency Cut Filter which can improve the clarity of poor quality recordings. The clarity can be controlled by setting the frequency cutoff point.
For no frequency filter set the control to None. For a mid level frequency filter use High or Low Bass Filtering or for very poor quality recordings use the 1500Hz strong filter. The default setting is for no filter: Full Bass (0Hz).
You can also right-click on the files you loaded into the program and use the Special Audio Processes to try and improve the audio.
You might also want to contact NCH Tech team and see if they can help here: https://www.nch.com.au/support/index.html
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