1. Using new config Select:
4. iGnative checkbox
5. iGnative options(under GPS)
6. Auto switch to GPS... checkbox is checked
7. Pause current player when voice... checkbox is checked
8. Open iG and set the volume to ANYTHING BUT 100% <-- VERY IMPORTANT!
That will pause it, but if you just really want to just lower the volume inbetween then add the following to you exectbl.ini file. And set the end values to how ever you want the volume to be decreased by, in this case 0-255 for 0-100% volume.
PS. Not to knock igmon as I have used it before but with the main features already included right in RR, it is kinda pointless to have two things that do what you are asking, when only one will be fine. The only advantage to igmon is that it can/will autozoom the map if you like it too, with extra CPU usage to go along with it, My .02 Cents...
You HAVE been helped...