By which I mean things that at the time you wouldn't think would be a problem...
Stereos - My 6-yr-old daughter has appropriated the portable CD player on which she plays her CDs that includes the whole listen with mother stuff that was around when I was her age as well as more sophisticated fare as Angelina's guide to classical music.
Not bad, an appreciation of decent music and rhythm is good for language and brain...
...
However, after the eighth play of 'The Wombles of Wimbledon' at 6 in the morning you begin to twitch a bit..
to the extent that you begin to hear the oboe at the start and you shiver
I tell you I'll be in a padded cell with a jacket soon, imagining Uncle Bulgaria, Tobomore and the rest surrounding me singing: 'Do do do de do, do de do do do dod do...'