Can running audio from a laptop ruin your mixer?

Question

We have a Behringer X-32 and two S-16 digital snakes. We were running our audio from a laptop (using a plethora of adapters--all passive--to go from 3.5mm stereo to xlr) to one of the digital snakes and then running a long cat5e cable back to the mixer. We noticed some "popping" in the speakers, almost like it was on a timer, there would be a regular "pop"--though not that loud--but noticeable, something that could almost be disregarded as a pop from a microphone.

Long story short: the ports in our mixer are now fried and we can't get a connection to the digital snakes. The screen on the mixer flickers when we try.

Port 'A' died after we randomly powered the mixer down to move it and fired it back up again. Port 'B' died after we discovered we had no control over the levels coming in from the laptop, so we rebooted the mixer to try and fix the problem, but when it came back on, the same flicker was in the screen as before and port 'B' was now dead.

One guess is that somehow we had inadvertently created a rudimentary capacitor somewhere that was building up capacitance and discharging it down the cat5e cable, which effectively killed the port in the mixer by death by a thousand cuts, but we're not sure. Another guess is that the signal from the Mac book was too hot, and fried the ports.

What could have caused our ports to fry? The only thing we did differently from other shows was plug the laptop into an XLR port in the snake instead of into the mixer using an RCA cord.

Answer 1

Behringer, for better or worse, has a budget brand reputation. This is, of course, to a good degree a consequence of their pricing. It can be achieved partly due to the specs of their products, but partly due to the part sources. As a consequence, Behringer tends to be disproportionally affected by supply chain problems like capacitor longevity scandals. They have several devices that are sought after and often the recommendation then is "get two, you'll need them".

Ethernet ports tend to be galvanically separate from the devices they are part of, meaning that they don't usually contribute to ground loops. But that may also mean that their voltage can move significantly away from the ground/earth of the devices. That can be problematic if capacitors between the various grounds tend to not have a lot of safety reserves with regard to overvoltage tolerance.

Where does that leave you? With Behringer probably even more than other brands, I'd read up on reviews, particularly of long-time users, before buying. I don't have particular experience or knowledge of your device and may sound like astroturfing, so try forming your own opinion of any device from any brand by looking for reviews with followups of the "after [not really satisfactory duration] the device died on me" kind. I don't even know the X-32 situation in particular, and Behringer produced a few affordable classics that are rather sought after.