Thank you for testing my game! I will do the same to yours soon :)
Does the speech bubble change? (Do you only see ** SPEAK **?) Normally, when you talk on the microphone, the speech bubble text should change. If it does not detect a microphone or you don't make any sound/noise for a certain period of time (in that case, game over), the text should be ** ERROR **.
I am not sure about other countries but in Japan, lightbulbs don't go to glass :) Sorry if it was misleading!