Hi MarcPC and Friend,
Thank you for contacting Slingbox Forum. I am sorry you are having connection issues with the Android device.
Have you completed the Internet Viewing Test on the home network computer at Slingbox Setup? This will need to say 'Ready for Internet Viewing' to be able to use remotely with a mobile device.
If other devices are working at remote locations, then it seems there may be an issue with the Samsung Galaxy Tab 8.9 accepting the Slingbox information. There may be a requirement it does not meet for viewing. In the following link, you will find the access to see the requirements for various SlingPlayer for Mobile Devices:
You may also want to reinstall the Android App to see if that will clear up the issue. The tablet manufacturer may have insight to a resolution too.
Hope this helps with your issue!
Have a great day!
Sling Moderation Team