Like Sean mentioned, try turning off hardware acceleration to see if that solves the issue.
If it does, then there are a few things to try:
- First is update your video card drivers. This would include any discrete video cards (nVidia, AMD, Matrox, etc.) as well as your Intel GPU drivers if your CPU has an embedded GPU. The easiest way to tell the latter is to look in Device Management and see if there is an Intel GPU listed under Display Adapters. Once all of the drivers are updated, enable the Hardware Acceleration again in the Smart Client.
- If updating all of the GPU drivers doesn't resolve the issue and you have an nVidia card, it is possible that the card is too low-end to handle the decoding. Essentially, it might be trying but just can't process it. To rule that out, close the Smart Client, navigate to C:\Program Files\Milestone\XProtect Smart Client\ and open Client.exe.config in Notepad. Do a search for "FallThroughPriority" and change the "AutoNvidia" to "OnlyIntel". Then save the file and try the Smart Client again. This will force it to only use the Intel GPU (if available) or the CPU. The full line you are looking for looks like this:
<add key="FallThroughPriority" value="AutoNvidia" />
If that resolves the issue then I would concur with our tech support that the issue is likely your video card. You can leave the setting at "OnlyIntel" so it doesn't try to decode to the nVidia card (it will still use it for rendering if the monitors are attached to it).