i play my ps3 on high defenition so i went to display settings and video output and then i clicked on HDM and its been working fine but now i want to change it back so i can play it back on a regular t.v that is not HDM i try going back to display settings and changing it back the way it was but when i click change the t.v goes black and then after 20 sec i shut it off and try it on my regular t.v but it doesnt work helppppppp