now about the heat... what type of 9 volt supply are you using, wall plug DC transformer, regulated...

I see you're using 7805, can be mount on a few cents heat sink or on the ground tab on your bread board.

I see often here in Canada DC wall plug transformer without any capacitor to the output... so a lot of ripple at the input of the regulator... maybe you get one of these !!!! simply add a large capacitor >1000 uF at the input this will maybe reduce the heat. If you can scope the supply line tell us what's looks like straight line or else. Can also 10uf + 0.1uf be added a the output of this regulator to avoid some oscillation.