Hi David,
I've just run a short test on my B2. I changed two radio channels, Presets 0 and 7 using the webUI just as you have done. However when I checked at Linux level (basically down in the engine room), the Prests 0 and 7 still showed the original settings.
However, when I pressed and held the 'Play/Stop' button on the front panel for a about 3 seconds, and got the 'Saved' message on the display, when I checked again at Linux level, the newly selected stations appeared on correctly on Presets 0 and 7.
I then powered the B2 down and back up. The new stations are still there on resets 0 and 7.
So, if you make the change to the Preset, then press 'Play/Save' button until the 'Saved' message appears, then hopefully this will resolve your problem.
Let us know how you get on.
Regards,
Peter.