A/V sync errors, lip flap, and lip sync errors, are terms used when referring to the annoying situation when the audio/sound does not match the video/picture. The severity can vary by video content. The delayed video takes longer to process than the audio signal, and it is especially true when processing high definition video formats. Many devices now have adjustable A/V sync or delay settings in their menu system so you can manually synchronize the audio and video.
One thing that you can do if your devices do not have A/V sync adjustments is to set the output video resolution of your set top box/DVR/cable box, to match the native resolution of your display/TV. Native resolutions of modern day displays are 720P, 1080P and 4k/3840 x 2160P.
Changing the Preferred Output Resolution on our DVR+
Please go to Menu>Settings>TV & Audio Setup>Display Setup>Resolution is the only choice on this screen. You must press OK to change the resolutions list white so the options are selectable. Next, navigate up/down to the desired resolution. When the desired resolution is highlighted in orange, press OK. The display will go blank for a moment to change output resolutions and then the video returns and will be displayed at the new resolution.
Changing the Preferred Output Resolution on our Stream+
Please press Home, then go to Settings>Display>Resolution>Now you can choose the desired video output resolution e.g. 1080p @ 60, 720p @ 60