Rightfax - fax quality

We're having a problem with the quality of faxes created via the Exchange connector vs. print direct to Rightfax. Faxes going through the Exchange connector are of obvious lower quality. There are definite quality differences that show up most dramatically for us when there is 'red' text (indicating credit amounts on invoices). This makes it unacceptable to our customers as they can't read the fax once printed on their fax machine. Is there any way to affect the fax quality going through the Exchange connector?