Issue started happening couple days ago, now it happened to me yesterday. SMS FC and no incoming calls from other HTC evo devices - the screen shows roaming mode while within sprint towers Err msg "Radio interference error". I strongly believe it is a an HTC evo bug that interfere with Sprint Network.
And it ain't application issue...

Anyone else have the same problem?

Try going to Settings>System Updates and updating the PRL.

Yeah here you go again with your none-sense "do this 1st"....dude, so some research before replying....

Its not nonsense and it solves a myriad of connection issues. Did you actually try it? Do you know what it does? I'm on 4 different Evo-specific forums, one of which is extremely active, and no one has reported having an issue like you are describing.

I couldn't get it to work and I tried what you said. I got a text but still can't make or receive calls. And it all started with the radio interference thing.

Still didnt work. Thanks for trying though. Texts only work every now and again.

Nevermind. Got it. Apparently there was more than one prl update to do.

Mine started doing it right after our big earthquake here in OK. Tonight it's doing it again even in swype. Last time I did what you said was befor the earthquake that morning. I'll try doing it again n see if it helps me.