Wonder if this issue has re-arisen on MX105 and latest FW. Currently it's on MX 18.107.2. Getting similar reports from customer that box frequently makes a loud wailing noise, so loud that even with door to room shut, they can still here.
Checked connectivity logs, and can see that there are a lot of drops visible. Have logged a support case, but haven't heard back yet.
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The other thing I've noticed is:
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Wondering if anyone else is seeing this.