Not sure what you mean by Sonos radio? I’ve used the TuneIn part of Sonos to play content for 13 or so years (I think...it’s been a long time, for sure) with no issues, I’ve occasionally used iHeart radio to play radio stations, I’ve set up direct links in Sonos as explained in the setting up an internet radio station FAQ, all with no issues. 

When I hear the phrase ‘all chopped up’, it makes me think there is some sort of transmission error between the radio station’s servers and the Sonos devices. Most frequently, but not always, it is due to wifi interference . 

There are a couple of things to note. Most streaming services use a different server to feed Sonos users than their web streams, so it is frequently hard to compare the two. Additionally, different streaming services have different tolerances for interruptions, so while a stream from Amazon may be fine, the stream from TuneIn may not. It all depends.

You indicate you have spoken with customer support, would you be willing to share what they told you? Or any specifics about what Sonos equipment you have, how they’re connected to your LAN, and which software version and revision you’re using? With data like that, you’re much more likely to get more informed suggestions on how it may be possible to change the current experience you’ve been dealing with for 7 years.