I've noticed that over time Miro's startup time gradually slows down. Even on a relatively high end system, Miro with 40 ish podcasts added takes >1minute to load to a usable state.
Using Procmon I've found that Miro is reading a large quantity of files from
AppData\Roaming\Participatory Culture Foundation\Miro\Support\profile\Cache
AppData\Roaming\Participatory Culture Foundation\Miro\Support\icon-cache
If I clear the contents of Cache, and all .JPG files >7days from icon-cache (which can be done on a timer using something like Belvedere from lifehacker) performance is immediately much better (<5 seconds to usable)
Question to Support/Community - Other than messing up the podcast favicons, is this safe? I've not noticed any detrimental behaviour but there may be a cleaner way of doing this.