We need you to be more specific. Your post is not clear enough and we need you to provide as much information as possible. If you have the SlingBox AV, you only can use the composite (red-white-yellow) or Svideo connection. We need to know how the Slingbox is connected to the network (hardwired, using a power or a wireless bridge) and also how the TV is connected to the Slingbox. It's also important to check the Internet Speed at the Slingbox location. In the meantime we recommend that you reset the Slingbox and then run the setup assistant to determine if the issue persists.
Let us know how it works.