Do they have a lens protecting the bulb from airborn grease, are your
sure its a 120v feed. Any oil will shorten life, I use a paper towel to
replace them, and alcohol to clean. Soft start I dought will help. It
could be cheap chinese bulbs, try a name brand like GE. I have seen tube
halogen 150 watt burn out from loose contacts making extreme heat and
cracking the bulb, look at the base connection, is it blackened from a
poor socket not making solid connection. Think about T8 flourescent,
they are really long life and save 75%-80% in electricity, nice for
undercounter with warm white bulbs. Pucks cost alot to run.