One of my favorite radio programs has died on SoundBridge :These 2 presets are for the 2 URLs that used to work for playing Sunday Baroque on SoundBridge (and still work OK on the PC):

1. http://www.sundaybaroque.org/listen/sb.asx
2. http://wshu.streamguys.org/wshu-baroque.m3u

One of these is taken from the Sunday Baroque web site, while the other I think came from the WSHU web page.

Can anyone suggest a way to overcome this problem?

I'll bet that the stations have changed their URLs; perhaps going to a "player" type. Try going to the PBS.org site (I think Sunday Baroque is a PBS program) and see if that isn't so. KMUN, up here on the northern Oregon coast, did that and now I can't connect to it either. NPR Hourly News changed its URL awhile back; I googled it and found a new URL that seems to be working now. I suspect the player thing is connected with the ubiquity of all these mobile devices now available. If I find a SoundBridge-working URL for Sunday Baroque, I'll let you know.

I think the previous post is correct. I run into this all the time. Try using the Rokusnooper or URLsnooper to find the direct stream. If you can find this, you should be fine. Some of the services use URL redirection and change their stream addresses every so often. The snooper programs lets you try the different audio streams in your Roku.