Sticky neck seal

Just noticed that the neck seal (latex) on my drysuit is starting to go
sticky - I don't usually use any sort of talc / spray / lubricant on the
neck (never needed it to get it on), but now I suspect not using it wasn't a
good idea... I'm going to try getting regular coatings of talc on it, see
if it gets better, otherwise it'll have to go in for a new one :O(
One thing though, is it likely to have gone like that (its only a year old)
just because it hasn't had any sort of talc or anything used on it for most
of that year, or would something else more likely have caused it? Being
left in the sun (not regularly, but has been occasionally just unavoidably
really)? It's usually dried quickly and used to be stored wrapped in it's
bag, although now I have somewhere to hang it. Any ideas on how to stop it
happening again so quickly would be good... :o)

David