program to stop speakers from going to sleep?

goshawk on horseback

hello all,
does anyone happen to know, if there is an accessible bit of software that will send a little sound to speakers, say once every 8 or 9 minutes?
I have got some new speakers that I use for my speech, but they have one very annoying feature, they go to sleep after a while if nothing is heard through them, which I find very annoying, and there does not seem to be any way of disabling that feature.
I also need to be able to select which sound system the sound comes through, as it would not be the default one.
hope that all makes sense.

Join to automatically receive all group messages.