I think John might have meant sporadic rather than spasmodic!
Anyway, I've said this before and I'll say it again - RNIB need to send a
blank test email from the account their papers come from, to
check-auth@xxxxxxxxxxxxxxxxxxx.
If the results that come back are not either "pass" or at least "neutral",
then that's where the problem will be. 99% of the time, that's why email
isn't delivered.
Incidentally, anyone can try this, and it's an interesting test - if your
emails don't get through, then ANY of the tests failing will be the reason!
