I took my 2012 RAV4 Base Model 2.4L in for 30,000 mile maint on February 8. Also had two TSB recalls taken care of: wiper motor link and rear seat belts. Ever since this visit I occasionally hear three beeps at highway speed. Its very soft, my wife kept hearing it and I finally did too. Frequency is unpredictable, but the last time we were out this past Sunday it did it about every 5 minutes over one particular 30 mile stretch. No warning lights, nothing seems to be amiss, everything running smoothly as far as I can tell. I called the dealer and inquired, they didn't know what it might be, wanted me to bring it in for inspection - I passed for now since nothing really seems wrong. Anyone ever experienced this ? Speculation what it might be ?