M-DMA-A (Dual Mic/Line Input Module) failure

Forums Forums iLive Forums Archived iLive Discussions M-DMA-A (Dual Mic/Line Input Module) failure

This topic contains 5 replies, has 2 voices, and was last updated by Profile photo of millst millst 8 years, 1 month ago.

Viewing 6 posts - 1 through 6 (of 6 total)
  • Author
    Posts
  • #23616
    Profile photo of 01soundman
    01soundman
    Participant

    I’d like to hear from the iLive community about something I hope is mere coincidence rather than a possible manufacturing or component defect.

    I’ve lost two modules within a month of each other. (Just replaced one a couple of weeks ago after failure at the end of January; the second failed last night.) Both are installed, along with 6 others, in an iDR10. Fixed installation in a church. Powered down between uses on Sundays and Wednesdays. System has been installed for two years this April.

    Thoughts?

    Not looking for ‘cheerleaders’ here. Nor am I trying to declare ‘the sky is falling’. But to say my confidence in the system is not very high at the moment would be an understatement.

    Ray

    #33429
    Profile photo of 01soundman
    01soundman
    Participant

    What follows is an update of where the above took me.

    The installer/seller of the system came to my site and we contacted the Tech Support folks for the US Distributor. After several minutes of discussion, I was asked to put the ‘allegedly defective’ module back in the iDR10 and test to see if it worked. Sure enough, it was fine.

    When I questioned why this was possible, we were told possible causes were:

    • The Phoenix connectors have “come loose” before and should always be checked to be sure the cables are not putting tension on them. (Connectors had been checked and replugged prior to call. All connecting cables have sufficient strain relief to put significant slack in each line.)

    • The card itself can ‘disengage’ from the planar/system board connector even though both mounting screws are firmly set.

    Their recommendation:

    • Check all connections monthly.

    • Unplug/reseat all cards annually to ensure this doesn’t reoccur.

    It may just be me but this seems unreasonable. It also seems to indicate that the card connectors are not fully seating in the planar connectors (in the back) and, therefore, point to a potential (mechanical) engineering defect.

    This particular iDR10 isn’t kicked around out on some stage floor or jostled in the back of a road rig. It’s a fixed installation; mounted in a rack on a concrete floor.

    Comments?

    #33638
    Profile photo of 01soundman
    01soundman
    Participant

    Just had the third M-DMA ‘failure’ in as many months. Reseating the card resolved the ‘failure’. So much for the “reseat all cards annually” approach; looks like I need to do it every 29 days.

    I’ve notified the US sales/distribution contingent of the failure and awaiting their reply.

    Starting to strongly suspect a defect in the connectors/planar in the iDR10.

    #33639
    Profile photo of millst
    millst
    Participant

    I have had the same thing occur with a line output module.
    Check it is not a dry joint on the board inside the IDR10.

    These systems are very similar to counter systems. The IT industry has this problem all the time.
    The solution in IT is to avoid powering down whenever you can.
    Avoid massive temperature fluctuations and regularly remove and reseat cards.
    Video cards on high speed Busses are particularly succeptible.

    #33641
    Profile photo of 01soundman
    01soundman
    Participant

    While I appreciate the IT industry reference (I worked for a major computer manufacturer for 33 years), I don’t see that it applies here. This is a unit that ships in a road case with casters. It’s meant to be “out and about”, making “always powered up” a bit difficult. I would think sitting in a rack as it is (see above) would eliminate seating issues.

    Said another way: If cards need to be periodically reseated or systems should always be powered up, why is that not also true for the desktop PC industry?

    If my desktop PC failed every 30 days, I would not be satisfied when Dell told me I just needed to leave it on all the time and/or reseat the CPU every month or so…

    #33642
    Profile photo of millst
    millst
    Participant

    Agreed, every 30 days is too much, that definitely indicates you have a problem.

    The occasional seating issue on cards is to be entirely expected though.

    Desktop PC’s for me are the worst. I now leave mine running 24 x 7. The big problem is when your Video card uses a different metal to the motherboard. This causes corrosion between the metals and eventually increases the resistance until the card becomes unreliable. Unseating and re-seating the card multiple times scrapes off the corrosion and allows it to work again. Some Desktop machines I have had have needed this every 2 or 3 months.

Viewing 6 posts - 1 through 6 (of 6 total)

The forum ‘Archived iLive Discussions’ is closed to new topics and replies.