Randomly Overheating Blackmagic Design Converters

Peter Bowers

New member
Jul 8, 2024
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Hi everyone. Hoping for industry wisdom on this one.

We have several Blackmagic Design Micro SDI to HDMI 12G converters which we've used on our events for a while now, but we've started having problems with them. Spontaneously one will overheat causing it to either flicker on and off or temporarily stop working altogether usually in the middle of an event.

Our setup typically consists of two TVs, two projectors and two floor monitors for presenters to see their slides. SDI cables are run from a Blackmagic TV Studio to each location either individually or looped from one converter to another depending on the layout.
  • Overheating has occurred on three different events on three different converters.
  • By overheating I mean you couldn't safely handle the converter for more than a couple of seconds without burning yourself.
  • Twice it's occurred to a floor monitor which is inside a wooden non-airtight bottomless box with the converter loosely left on the floor. The ambient temperature in side the box was warm but not hot
  • The third time it occurred to a TV on a truss, but again the converter was on the floor, not touching any metal or other equipment. In this case the converters SDI Loop out was used to another converter.
  • Each time the converter overheated it was swapped out with another which worked normally for the rest of the event.
  • The first two converters were returned to the office and tested with no issues. They were then used on subsequent events without issue.
  • The USB-C power transformers which powered the converters were also tested and worked fine on subsequent jobs.
Does anyone have any experience of this or advice on methods to avoid this happening. Blackmagic Design's support team had no answers for this situation. I've seen other similar forum posts which don't speak highly of these converters and recommend different brands, but I wanted to see if there was anything specifically we could be doing wrong before exploring that avenue.

Thanks in advance,
Peter.
 
Not a video guy at all but I'm curious if this depends on the type of file that is being feed to the convertor. I do know that compressed files are strongly discouraged in audio playback systems as the computers may not be able to decode fast enough to read the cues.
 
It shouldn't as there's no files involved, just a datastream carrying 1080p25 video with embedded audio (although I'm not using the audio part as that's been fed separately to a mixing desk). The converters just convert the data/cable standard from SDI to HDMI. All the converters are designed to do this with no compression and unnoticable lag.
 
Intermittent issues, especially where there's no obvious common factor, makes me question what the rest of the system looks like, and if there's a potential common factor that's not obvious. In this case, given the high case temperature involved, I'd be looking for something power-related (either on the source side of things, or on the load side of things). I could see scenarios where a bad HDMI or USB cable, or combination of cables and equipment, could cause the observed behavior.

Not sure you'll be able to find a definitive source of the problem without being able to reproduce the issue on command, though. So my next steps would probably be to take a broader look at the system if it happens again - try setting up the exact same system (including cables, power supplies, monitors, etc.) back at the shop to see if it is reproducible in a controlled environment.
 
Intermittent issues, especially where there's no obvious common factor, makes me question what the rest of the system looks like, and if there's a potential common factor that's not obvious. In this case, given the high case temperature involved, I'd be looking for something power-related (either on the source side of things, or on the load side of things). I could see scenarios where a bad HDMI or USB cable, or combination of cables and equipment, could cause the observed behavior.

Not sure you'll be able to find a definitive source of the problem without being able to reproduce the issue on command, though. So my next steps would probably be to take a broader look at the system if it happens again - try setting up the exact same system (including cables, power supplies, monitors, etc.) back at the shop to see if it is reproducible in a controlled environment.
Thanks Rob, we're planning to set everything up back at base as you describe, scrutinising everything, hopefully something will become obvious.
 
You’re in the UK, right? Are you sure that you don’t have an extension cord with Earth and Neutral swapped in the plug? The neutral current might be going through your convertors…
Thanks Peter. Everything we use has been professionally tested and passed a governmentally required test (PAT). An Earth/Neutral fault would definitely have been flagged. Of course the outlets could be at fault and we have no control over that but as it's happened in 3 different locations it feels like the chances are slim. Also, wouldn't I have been electrocuted? :unsure: