DSP expansion unit for Mitel / MiVoice Office 400 systems. The SM-DSPX2 contains two DSP chipsets to add voice processing resources. It supports DECT, VoIP channels, Fax over IP (T.38), G.168 echo cancellation, voice message compression (certified), and GSM integration (certified). Some resources require licenses; DECT, FoIP, and some FXO resources are available without an additional license according to the product documentation. Compatible with MiVoice Office 415, 430, 470, and MiVoice Office SMB Controller.