ML/EL random ringing on ONS ports early in the morning then stops. I know maybe a failing card. Anyone familiar with serial #'s from a bad lot?
This issue goes back to 2005/2006.
Mitel had a manufaturing problem that caused the slics on the cards to overheat and crack.
I believe all the defective cards serial numbers began with AA B. We had a lot of bad cards with AA BGN as the start of the number.
I am pretty sure all the bad cards had a revision level of C1. But it has been a long time and my memory fades.
The random ringing you speak of does not sound typical of this kind of cards failure. The bad circuits would lock out and have no dial tone.
Your issue is odd becuase it is time of day sensitive. Are you sure it is not a wake-up call issue? Make sure someone did not schedule recurring wake ups for a bunch of extensions.
I have run into the random ringing problem several times but have never had a card in the pbx cause it. Here in the South the humidity is high this time of year and many of the motels and offices keep the rooms nice and cool. I have had moisture condense in the wall jacks and turn the connections in them green with corrosion. This has caused rooms to pulse dial numbers at random. For some reason it has always seemed to happen around 1 or 2AM. Watch for lights to flash on the ONS cards this will tell you what extension it may be comeing from. Another clue to this problem is when some of the random ringing calls are answered all you hear is a lot of static. You may have to teach the people at the site to go and look at the lights on the cards when the random calls start. Have them write down the card and number of the light they see flashing. Good Luck