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Community Member

Intermittent and Brief flashing Mic LED SPA921

Hey folks, I have posted this in the switching community in the SB area but thought I might have more success here.

I got two new switches (SG200- 26 Gb) to replace a single unmanaged one. This problem occurs on the new switches. Even factory reset and on both switches. I have tried turning auto neg for port speed and set to to 10 full. I also tried Turning off green ethernet and STP.

The Linksys branded SPA921 have been intermittently and randomly and briefly having the Mic light flash red a couple of times, which I know is the light to show loss of network connectivity. But it flashes only for a second at most and could keep doing it randomly but for a while or may just simply do it once or twice then not do it for a while. It seems to do it only (prefer) on one or two phones randomly, some of the phones don't seem to have the issue.

Its obviously the new switch that is causing it but for the life of me I dont know why.

Any things to look at I would DEEPLY welcome as I was meant to be off site a week ago haha.

Thanks for all your help


Community Member

Intermittent and Brief flashing Mic LED SPA921

Hi Liam.

Just bought a SG300-10 and a SG300-28, moved an old SAP921 and had this problem.

After some tweak on the switch (based also on suggestion from your other post) and upgrading SPA to latest firmware I solved my issue.

Here what I did:

interface gigabitethernet8

no eee enable

speed 10

negotiation 10h

spanning-tree disable

spanning-tree portfast

spanning-tree bpduguard enable

switchport mode access

switchport access vlan 10                           

no eee lldp enable

no green-ethernet energy-detect

power inline never

no macro auto smartport

Not sure what is the right command, but my feeling is that led stopped flashing when I shut down smartport.

Hope this helps.


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