Check the following:

1. Image Quality
   Ensure that the inserted image file has a suitable resolution for the presentation.
2. Compatibility Format
   Check the compatibility format of the image file.
3. Trust Center Settings
   Open and review the Trust Center Settings.
4. Zoom Level
   Adjust any zoom level settings during the presentation.
5. PowerPoint Version
   Check the PowerPoint version and ensure that it is compatible with the image file format.