Private message traffic? how can we make it happen faster

Ive had this posted via a forum member. Ive looked and cant find anything that i can do to or advise...
PLEASE HELP

Hi guys,

From time to time I've noticed that PMs can take a long while to leave the outbox, other times seem to go as soon as you've clicked "send".
I've noticed again in the past few days that PMs seem to be really slow to move. Specially before mid afternoon, maybe its just me...

We all know that PMs only leave the outbox when the intended recipient is logged on to the forum. Fair enough - they wait in the outbox until the recipient can receive them.

Also PMs won't send if the sender's sent box is full or the recipient's inbox is full, also fair enough.

But if the PM mailboxes are ok and the sender and recipient are online, what triggers the send/receive of the PM?

It'd be good to get PM's to flow a bit (lot) more smoothly than they sometimes do.
Does anyone have any idea why the time to receive PMs can be so variable?
Is there a forum setting that clears PMs at certain intervals or something?

PM's leave the outbox when the user reads them. Not when the user is logged in.

There is no option to make the PM flow faster.

Cheers Mario, thats what i thought from the info available, i just wanted to be sure i had it correct prior to responding.

Legend cheers