Hi John,
You cannot delete Presets but can overwrite them with other stations.
To find other stations you will need to use vTuner on the web UI page - click the vTuner tab and type Radio 2, for example, into the Search box > stations with names including Radio 2 will be listed in the panel below > click on the play symbol (arrow symbol to the left of the search result) to check the station plays OK > click the three dots to the right of the search result and select a Preset to save the station to.
You haven't said which brennan you have.
Paul
Brennan Support.