Magnepan MMGs Crackle Sound


I was listening to an album I had never heard before and I noticed a crackling sound coming out of the speakers.  I confirmed it wasn't actually part of the recording by listening thru headphones.  What I don't understand is I don't hear it on anything else I listen to.  Since I'm not the original owner of the speakers, I contacted Magnepan to get the build date, which was June 2008.  Seems like they aren't old enough to go bad after 13 years.  I've had them for about 2 months. I don't drive them particularly hard.  Max volume in my room is around 88 db.  Anything over that is too loud for my ears.  My question is how can I troubleshoot the issue to confirm they need to be fixed.  I don't want to ship to Magnepan unless absolutely necessary. I know it's not a component issue because I hear the same thing in my office system when listening to the offending album.
terrapin77
Magnepans don't usually crackle, they slap or buzz (loose wire). I did have a tube amp that didn't work with my MMGs. Just on one place on one CD, it just didn't like what was going on. I swapped amps and it went away.  
@russ69 Crackle might not be the best way to describe it. I have never heard the sound before so it’s hard to describe. It was a recording of Ambient music made with a bunch of synthesizers. It could be described as sounding like static you might hear on the radio but not as full.
If you hear the same in your office system then the problem is not the MMGs!
@yogiboy I forgot to say that I moved the MMGs into the office. Easier to move the speakers than to move the components.
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hair or bit under the slip cover, that is touching the panel, or an intermittent separation of panel and support structure. Possibly a few other things...(on the list of potentials)

You’d have to play the offending part on repeat and then listen to find out exactly where it is coming from, note that..and then the cover comes off to inspect the offending area..

a fairly common experience when trying to diagnose panel speaker problems. (apogee ribbons and Martin Logan, others) the Martin Logan thing is fun as it can be a short/open on the given stator....(exceedingly rare, though)
I moved the speakers back into my listening room and was able to figure out the issue.  It isn't the speakers.  I stream to a Raspberry Pi 4 with Volumio.  The renderer I was using to connect to the Pi is the issue.  When connected thru BT, it plays as expected.  Not sure why the renderer has an issue, but I will contact the Dev of the app so he can troubleshoot.