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SF300 Combo Port not detected correctly (?)

Model -     SF300-24P

Mode:       Layer 2

Boot Ver:

Firm Ver:

The SFP ports are both empty - we have never plugged anything into the SFP ports.

Port GE4 - one of the Combo ports with SFP and RJ45 connectors -

Whenever anything is plugged into the copper (RJ45) port, the switch changes the

port status to "UP" -- but it kicks the Port Type to "1000M-ComboF", which is Fiber.

This, in turn, forces the port to 1000/F, with auto-negotiation disabled.

Naturally, any 10/100 devices will not work in the port because of this.

The only communication we can get in or out of the port is if we change the

adapter settings for the attached device to 1000/F.

So far, the other Combo port (GE3) seems to be working fine.

I have tried bringing the port down administratively, changing and saving settings,

as well as physically unplugging the cable from the port.

Each time, regardless of the device attached,

the port reverts back to Fiber instead of Copper.

Note that this condition has persisted through firmware and boot code updates.

My initial thought is hardware related - either the sense pin inside the

SFP connector has become grounded somehow, or the IC that handles

the sense signal is somehow knackered.

Has anyone else seen this behavior?

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