Hi Scott,
I think you're on to the answer. Your new Emo pre/processor tuner is perhaps HD ready. One of the capabilities of the latter is to allow a broadcaster to digitally send out a group of different signals, which the digital tuner will sort out.
When I lived in Toronto, there were early experiments in digital radio broadcasting using a system from Europe. If memory serves, it would enable a broadcaster to multiplex up to 16 different digital signals in the same bandwidth formerly occcupied by a single analog FM radio channel. The system was never adopted in Canada because the US had reserved the frequencies for military use.
Anyway, the current HD radio system in the US is an in-band on-channel, so the digital signal piggybacks on top of the analog FM signal (at a much lower level). If your EMO detected the digital signal, it would switch over from analog to digital. I think it would flag that on the pre-pro's front panel with an icon or something "HD", which might explain the different ad content.
Regards,
Alan
