Okay, we know that there 's a render problem, but no information has been given about:

• the Vegas Pro version and build that you are using;
• the media on the timeline that you are using;
• the render template and render settings that you are using;
• your computer's specifications (inc. CPU details and the GPU's specs);
• the OS version and build (e.g. Windows 11 24H2)

Please see https://www.vegascreativesoftware.info/us/forum/important-information-required-to-help-you--110457/ and provide the requested information to better the chances of getting a targeted response rather than getting wild guesses which is the best that you could expect right now.