I thank the experts in advance on this board for sharing their knowledge. You know who you are.
1. While sitting in traffic, I scanned the FM dial. My entertainment system classifies WXRT as "Rock." It also classifies WLS-FM as "Rock." WLIT if I recall is "Lite Hits." Okay. Who labels these format descriptions? The stations themselves? WLS-FM technically plays a lot of rock but their formal format is classic hits. WXRT is Adult Alternative. My system doesn't think so.
2. I have noted for a long time, while a song is close to ending, the title and artist of the next song is listed before it's heard/played. Does each radio station send a coded signal to automobile music systems? This applies to many music stations.
This delay became more prominent when stations added the HD Radio subcarrier to their standard FM signal. It takes 8 seconds for the digital encoding + decoding of audio for HD Radio, so stations have to delay their analog audio so that when a receiver flips between digital and analog there is no noticeable time-shift in the programming. The FM RDS (a.k.a. RBDS) data stream that updates your radio display (not the HD Radio data) has far shorter delay, and most stations donít add a synthetic delay to that RDS data stream. So, you might be seeing whatís next by 8 or so seconds before you begin to hear the next song.