Apply a high pass filter to remove any unnecessary low frequencies and a low pass to remove any unnecessary high frequencies.

Use sweep EQ with a narrow bandwidth to find any weird and out of place frequencies that stands out too much. (Be careful not to apply a very high boost to the narrow bandwidth which would make anything sound bad.) and then remove them with notch filters. Don't over do it.

Listen to to see (hear???) if there is any problems like the audio being too dark, muddy, boxy, bright whatever and EQ to correct those frequencies accordingly.