Spoof .wav as 'microphone' input

Is there a way to fool programs which expect input from a microphone to accept a .wav file? I am using Windows XP.

I have a heart rate monitor (Polar F11) which allows you to upload data via an acoustic link - you have to hold a microphone close to the back of the HRM while it chirps away. The problem is that the chirping is not very loud and susceptible to extraneous noise so the process is frustratingly prone to failure. It’s not just me as can be seen by the companies own user forums and bad enough that I would hesitate recommending Polar products to others.

One solution is to record the chirping to a .wav file and then play back through the speakers at a higher volume, holding the mic up to the speaker. Seems to work at least a bit better than the normal method, but you still need to be careful. I would be helpful to use the recording more directly.

Could you run a cable from the speaker out (or line out) jack to the mic jack?

I was looking for a software solution and hadn’t thought of this. Does anybody know if this would work? Would the mic input explode:eek: