That might be a bit more technical than can be answered here. You might try calling Magix support. They are going to need more specifics such as the type of camera, the actual program version and so on.
The only thing I can think of is that either something else on the computer is running and interfering with the data stream or there is an incompatibility with the format data. Either way, support is really the only thing that could help.
Supports number is 305-722-5821, Miami, Florida area code