Verifone vx570 settings

Faxing over VoIP

VoIP Mechanic recognizes that not every fax machine comes with implicit easy to find instructions for slowing down the BAUD rate to 9600. Adding to this problem is that most recent fax machines transmit at higher speeds than 9600, so we have started to list some fax model's instructions to lower the transmission speed to a baud rate of 9600. We recognize that these instructions can be excluded from many of the manufacturers manuals and can also be difficult to locate from any source, even when calling your fax manufacturers support personnel. So to try to alleviate some of the VoIP frustration in achieving this important setting, we have decided to try to list some instructions to lower the baud rate to 9600 for some fax models.

G711 or Non-Compressed Codec

First make sure that your VoIP connection for you line that you fax on is set to G711. This is a non-compressed codec. G729 uses compression and will make the fax fail. Some providers have a "Bandwidth Saver" setting. This would be a compressed codec. Make sure this is Not enabled. If you do not have access to this setting call your provider and make sure your connection is set for G711.

Why you need to lower the baud rate to 9600.

Faxing over VoIP can present certain challenges which require a slower transmission speed, so that most of the data get to it's destination. Packet loss, jitter, and latency all add up to corrupt a fax transmission over VoIP. When a fax machine determines that data is lost, it will shut down the transmission, even though with some bits of data lost you would still have a workable document. By slowing down the transmission speed to 9600, you increase the probability that most of the data will make the trip.

Lowering the Baud rate on an HP6110

You can set the Baud rate by following these steps: