... operating system. VIDEO AND AUDIO MDVR FERATURES AND CAPABILITIES 1, support 1 ~ 8 way real-time audio and video recording: 2, support ... the SD card automatically covered, protect alarm video7, supports 8-way recording8, support the playback of audio and video synchronization9 ... front panel 20 ,can upgrade software version through U disk or hard disk 21, support timer turn on/off Function22, support the ...