i searchbarred for you and found this from I_Am_God in another thread about cleaning liners
*next time make sure to wear clean socks every time, also take good care of your feet and make sure to always dry your liners after skiing, you shouldn't get smelly liners if you follow these simple rules....
now your best bet would be freezing them, then febreze and airing them out ....
if it's really desperate you could try handwashing them with mirazyme, this is an enzyme based washing product that is completely safe and will remove bad odors on a biological way....
you can find em in the better sports store...
also good scuba diving shops tend to have these ...*
i would post the link to the thread but 90% of replies are idiotic.
you could always phone up FT and ask which way they recommend doing it without just buying new liners.