R8 alerting on wrong band

I bought a new R8 for my new Outback earlier this summer and programmed it for Ka 34.7 only. I then noticed it would alert consistently to a fixed 33.8 source near my local Costco, but never to 34.7. I reprogrammed it from scratch a second time and got the same results.
I've not updated firmware but will do so this week. Just wondering if anyone else has seen this behavior