Hi,I have two devices 12v 0.18a and 12v 6a(max) and I powered those devices through 12v 2a adapter but that 2 devices didn't work properly.but if I powered one device (12v 0.18a) through 12v 2a adapter it worked more efficient.please say.. what's the reason for 2 devices not working properly?what can I do?please..