[Rob2005]

..just pressed the other main buttons and I can't remember which ones worked before, but they seem to be working faster for me:

help button - menu is instant.
interactive button - still takes about 10 seconds to load, but a bit quicker than it was.
favourites button - loads instantly.
on demand - takes 2 seconds to load, which is faster than it was.
guide button - as said, takes 2 seconds to load, then when pressed again is instant.
settings button - still does not work.