eBay Sign In Problems

eBay seem to be having some more issues with their account sign in facility.

When I sign in I always check the box "Keep me signed in today" so that I don't have to keep signing in (obviously).

But throughout the day I have to keep signing in.

Sometimes I might sign in, sell something then attempt to do something else and I get asked to sign in again.

I don't have this problem with other websites so I presume it is their problem, not mine.