I installed a QT-5140 DVR with 4 cameras and the system is working fine; however, after the whole setup was completed, in just two occasions the Image sequential mode worked fine, but when I decided to switch it from TV mode (Video) to PC VGA mode, the images stay static on the screen instead of showing them sequentially as required. Though I have been going back and forth trying to make this sequential action, nothing changes the 4 images on the monitor. I have been reading the CD manual, but I don't find any information about it. I wonder, what I can do to make the 4 images existing on the monitor to be replaced sequentially one after another as needed?