Hi, everyone! 
  
  
For two buildings in the past twenty days happened to us that the PC-based system with card NV8416T and  NV series software (V7.9.0.0029) to switch from PAL to NTSC and the picture on analog cameras can not be viewed. After the switch back to PAL system everything is working normally. PC is powered by the UPS. 
System configuration is: 
  
Motherboard: ASUS P875-M LE 
CPU: Intel Core i3 
Graphics: VTX3D HD7750 1GB 
MEM: 4 GB DDR3 
HDD: 3 x 2TB 
Power: 430 W 
OS: Win 7 Pro 64-bit 
  
Card: AverMedia NV8416T 
  
On one system is connected to 16 analog cameras, while the other system is connected to 11 analog and 5 IP cameras.