Yes, many times over ssh, when something tries to resolve hostname for an IP address from which I am connected. Because there is no PTR record for such address in most cases and this stall appears only from time to time I suppose that it is something broken with DNS resolving on given target machine - underlying resolver doesn't return NO RECORD immediately, but tries to find it somewhere to no avail until timeout. Usually regular DNS queries for for example A or CNAME records work just fine - ping some-well-known-domain.com works as expected.
