By clicking clicking on any of the medias the Media details appears. There you can change the basic player settings. As you see in the picture below there are options such as "Autostart", "Replay", "Social Sharing" and "Allow Download". By marking or removing the checkmark you disable or enable the features on the player. Moreover, under Preview and Share section you are provided with direct links to your media and also the iframe code of the media which is used for embedding your video on your desired web page.
Please note that if you change the player settings via the GUI, the changes will only apply to that specific video iframe code and not to all the videos. You can of course use the modified iframe code for embedding the video. However the changes will not be saved on QVP. If you would like to have your own default settings and save them please contact support.