Benchmark has developed SMPS for audiophile applications which has much lower noise and RF emissions than better LPS. See https://benchmarkmedia.com/blogs/application_notes/152143111-audio-myth-switching-power-supplies-are-noisy
Hi Emaile. Thanks for a great report.
In the other 4 cases, you connect the switch to Extreme using fiber, but with the M12, you had a somewhat convoluted setup (a) with copper - fiber - copper to M12 and (b) use copper to Extreme instead of fiber.
Can you throw some light on why pls?