For anyone wondering, do the following:
find sendfax.conf (VMWARE version is under /var/spool/hylafax/etc) file and add the following:
View attachment 5313
The VRes value specifies 196 which is medium quality. This will improve the quality for the faxes you send from AvantFax. (There is a -G command that can be used which specifies to use the best quality available from the machine's end user. I'm not sure how I would use that. Maybe removing the 196 and simply adding -G in this same file. For anyone who might know please let us know)
I'm not sure how much this helped since I did both changes at the same time, but under /var/spool/hylafax/etc edit pagesizes. Scroll all the way at the bottom and comment out the default size. Then uncomment the second default one (This is the North American Letter size. Assuming you are using this size and you are from the US)
View attachment 5314
Stop and start again hylafax service using: "service hylafax stop" and then "service hylafax start" (Without the ""). Then make sure that hylafax, faxgetty and iax modem are up using the pbxstatus command under root. It's important you restart hylafax to apply changes.
The quality from my faxes improved dramatically. They are the same quality as my standard landline faxes. Which means I'm removing my landline contract and moving it to the cloud to get the best bank for my money.
Can't wait for the day fax is dead. Until then, I hope this helps others and saves them time troubleshooting!