There are two solutions:
1. Check whether the interface connection between the cable TV signal and the set-top box is firm, which can sometimes be solved by rotating the connector;
2. Follow this line to find the last interface of the wired signal and see if the link is loose.
Digital TV is an audio-visual system that compresses, codes, transmits and stores moving images, sounds and data through digital technology, and sends and plays them in real time for viewers to receive/play. It is a digital system from program collection and production to program sending and receiving to user terminals.
The system uses interlaced scanning, much like the standard NTSC scanning method. It scans one field every 1/60 seconds, with 539.5 lines, and generates 30 frames per second. Proponents of 1080i claim that it is the only system that can produce real high-definition TV pictures, while all other systems with fewer scan lines are only ATV systems.
1080i system scans multiple lines, which greatly improves the resolution of TV pictures. But in the end, we know that the quality of the picture depends on the original picture quality. How well it is kept in the whole production process, especially in the real signal transmission process, forms the final picture seen by digital TV.