Chrys pointed this thread out to me as I have a growing thread on my own forum showing what testing has been done so far.
Im not with TSO but I am with Vidahost. Both are both part of Paragon Group. Mail to my server also goes via the MISP cluster.
I raised a support ticket last night but atm Im still going round in circles because at first they think its something on my server which I don't believe it is.
I'm not sure what packages you guys are on, but Im dedicated server with full WHM. (I know that their cloud services dont allow stuff like CPanel) so Ive been able to test to some extent and turn things like Spam Assassin off and make changes to DKM. Ive also whitelisted @plus.net - none of it makes any difference.
The latest info on my ticket is the guy said from the logs he cant see any of the missing ones ever being received at their end.
btw.. Im also having the same problem using BT, which is also powered by Lithium.
Edited by kitz (Sun 10-Apr-16 18:17:31)