Hi Shahid, We appreciate your feedback on Prime and YouTube Videos that are unresponsive, and for optimal performance, we ask that you please ensure you've got the latest firmware version installed on your DU6900 TV. You can check this by going to Home > Menu > Settings > Support > Software Update. You may also want to further optimize performance with the self-diagnostic tool, which checks memory, frees up unused cached memory, and closes background apps. Go to: Home > Menu > Settings > Support > Device Care > Start Device Care. If you’re experiencing issues with the Wi-Fi connection, we suggest you try the following: 1. Use 5Ghz Wi-Fi if possible 2. Try wired LAN if available 3. Try repositioning the router so there are no obstacles between your TV and the router 4. Try running a cold boot on your TV. To do so, hold down the Power button on the Samsung TV remote until the TV turns off and then on again. This should take about 5 seconds. If you need more help, Samsung is here for you! Please call us at 1-800-SAMSUNG, 8 AM - 12 AM EST, seven days a week. Our LiveChat agents are also available by clicking on the ‘Support’ link on our website. ~ Samsung Advisor

Hi Kiki927, Thank you for purchasing the Samsung DU6900 Crystal UHD TV. I am happy that you are enjoying your new TV with features such as Mega Contrast, allowing incredible details to be revealed, drawing your eyes to the most important parts of whatever you’re watching. If you should have any questions or concerns with usage, features, or how to best optimize your settings, Samsung Customer Support is here to help. You can call us at 1-800-SAMSUNG, 8 AM - 12 AM EST, seven days a week. Our LiveChat agents are also available by clicking on the ‘Support’ link on our website. ~ Samsung Advisor