Overview When attempting to call toll-free numbers, users may encounter a 503 Service Unavailable error due to an 'Invalid Line' in the SDP message. This issue can arise if IPv6 is enabled on the netw...
Overview When experiencing one-way audio issues on internal calls from a Voice Operator Panel (VOP) system, it may be due to a codec mismatch. The VOP client might default to a codec like G.722, which...
Overview Users at a specific site are experiencing issues with a speed dial shortcut (0 dial) that results in a fast busy signal. This issue occurs when the speed dial is incorrectly configured to rou...
Overview When factory resetting Yealink T48S phones, users may experience a loss of configuration and a no service error. This issue can occur if the phone is using an outdated provisioning URL or an ...