FAX-2580C FAQs & Troubleshooting FAX-2580C Not your product? Sort by: Updated Date Popularity 2 Results 1. 05/15/2013 I am using Voice Over Internet Protocol (VoIP) and I'm having problems receiving faxes. 2. 04/25/2013 Why doesn't the machine answer when receiving a call? Fax FAQs & Troubleshooting