Key combinatiosn causing blackscreen using IPAC4 and Windows XP - MAME

[kahlid74]

I'm wondering if anyone has seen this before.  The computer is running Windows XP and an IPAC 4.  Player 1/2/3 all have happs competitive joysticks for four cherry switches and player 1/2 have six buttons.  Player 3 has four buttons.  When Player 1/2/3 are playing a MAME game some type of key combination is pressed and the screen goes black.  MAME is still running behind the scenes but I can't get it to come back into focus.  I can CTRL ALT DEL and then end task on MAME.exe but explorer then doesn't come back.  I usually have to do a restart. 

I haven't started digging to deeply into this but is this a key combination that's causing Windows XP to freak or is MAME freaking?  I'm using the default IPAC4 key configuration.  Should I use a custom one?  What keys specifically should I change?

[kahlid74]

Booo no one?

[lanman31337]

I'm trying to think what caused that with me, it was something with player one and player three causing me issues.  *thinks* I think alt tab causes a hiccup, or was it alt enter?