
1) Make sure that you have installed Adobe Flash Player for your internet browser and there's no torrent | p2p program / internet bandwidth hog application running in the background.
2) Check if ActiveX and Java are enabled (refer to your internet browser documentation for the steps).
3) Try to use other internet browser such as Mozilla Firefox and Opera if you're using Internet Explorer.
The troubleshooting pretty much involves diagnostic steps to identify the nature and causes of the problem. If the problem persists, contact your internet service provider and confirm if the problem was their responsibility and not misconfiguration of your computer settings. Service by poor ISPs which provides unstable internet connection is also a main contributor that leads to this undesirable situation.