Default Problem with recovery on Allwinner A13

Hello, I have an allwinner A13 with broken screen, and I want to test it before buying another one, yesterday I installed CM 10 trought recovery(Gettin in with "adb reboot recovery"), but today ADB disabled itself(Yesterday was working with CM10) and I can't get into recovery, I try Vol+ & Power, but tablet gets into a extrange USB mode, same with Vol- & Power and I have no more buttons, how can I get into recovery? This doesnt work