OK. I have a couple of ideas. Give me a few days to try this one for you. We use the ISD5008 voice recorder IC all the time. I have never tried this but I will check to see if I can modify a program to output the incoming audio directly to the speaker. If so, it's a piece of cake. Releasing the activate button will have the PIC set the ISD chip into playback mode and jump to a memory location that has a prerecorded sound effect (of your choice). If the ISD won't allow this, there is another route to go but at this point I have very limited experience with a new ISD chip the ISD1700 series. With this chip, the incoming audio automatically outputs through the speaker during record indicating you have reached the end of the memory array. In theory, the chip could be addressed purposely to the end of the array. Incoming audio outputs through the speaker. When the button is released, the PIC puts it into playback mode and jumps to a location with your prerecorded sound effect. Again, I just began dabbling with this device and, being a different animal than a '5008, may take LOTS of time figuring out this one. Again, give me a few days to try the '5008 way.