Video quality can be due to a low cellular signal, weak wifi connection, so the best thing you can do is to ensure your internet connection is strong and reliable for streaming video content.
If you are unable to make improvements to your internet connection, you may be able to adjust your video quality on the video itself by clicking the HD icon (desktop only). Lower pixels such as 270p, 360p, or 540p will have the lowest video quality, but will help to ensure you're able to stream using a weaker internet connection.
Higher pixels such as 720p HD will offer the best video quality, but may slow down the speed or cause "buffering" issues if your internet connection is weak. If this happens, we suggest lowering the pixels (sacrificing video quality) or setting your video to "Auto" to automatically adjust video quality based on your internet connection speed.