Paul,
I haven't listened to the audio yet, but if there is persistent background noise issue, the noise reduction tools does a good job. Leave yourself 10 seconds of more of dead air at the beginning andor end of the audio. Select this dead air area, click noise reduction then click 'get sample'. Select the entire track, click noise reduction then click apply. It removes the noise in the back ground pretty well.
If the issue was playback streaming and you want to cut down the file size, go to a lower sampling rate. IIRC, the default is 128K but 96K is better than CD quality and for the net 44K is more appropriate and still very good quality.