Hi Patrick,

Thanks for support,

Can you please make an audio recording of a call so I can hear the hum? [send to paborn at Cisco.com]

yes i send you a registration this week

Is this new equipment or has it been previously configured and used successfully?

yes

Approximately how long does it take before you hear the hum?

not regular time, sometimes after 1 day at times after 3 days

Is the hum heard only on one SPA942, or will any SPA942 experience the hum?

no, for all

Does the hum occur if you use an analog phone connected to either FXS1 or FXS2 of the SPA9000?

i test this one this week

Are all SPA942 phones using PoE?

no i connect one for test with power supply (from my spa941)

Can you test with a SPA942 using a power supply instead of PoE?

yes i test this one

Does the hum occur during every call of appropriate duration?

every call, i hear hum and the caller will hear to low, I have to speak into the microphone attached

Is rebooting only way to get rid of the hum?

yes

Does the hum appear to be heat related?

?

Is the hum heard on internal, phone to phone calls too?

no internal are ok

Is hum heard with inbound calls, calls from PSTN to SPA9000 system?

Is hum heard with outbound calls, calls from SPA9000 to PSTN?

both

When you reboot the system, do you reboot the SPA9000, SPA400, and SRW208P?

If yes to #15, can you try:

a .reboot only the SRW208P and test?

b. reboot only the SPA9000 and test?

c. reboot only the SPA400 and test?

only the spa system, don't reboot switch

Wednesday i go to office when spa are installed and test all your question.

Thanks

Best regarde

Thomas

Hi Patrick,

i have reset a system completely, connect SPA400 Direct to SPA9000 in ethernet port (configured bridge mode), i connect e siemens analog cordless at fxs2.

if a call with one of four spa942 there is a hum in voice and silence in the background

if i call with cordless connect in fxs2 the voice are clear and ok

i test the system for othe 2 day and update the post.

Thanks

Thomas

Hi Thomas,

Thanks for testing and providing the additional information.

Because you say that FXS > SPA9000 > SPA400 > PSTN = no hum, I want to say that the SPA9000 and SPA400 are good.

Because you report problems on all 4 SPA942 phones, I want to say that the fault is not on the phones, but probably something common to all phones.

Can you please make an audio recording of the noise, "hum in voice and silence in the background" and a recording of a call on the FXS so I can listen to a good call and a bad quality call for comparison?

Please confirm who hears the hum, the person on the SPA942 or the external person?

I am intrigued that all 4 SPA942 phones have the "hum" regardless of their power source, PoE and external PSU. Please send me the configuration of:

SPA9000: https://www.myciscocommunity.com/docs/DOC-3027

SPA400: https://www.myciscocommunity.com/docs/DOC-3155

SPA942: https://www.myciscocommunity.com/docs/DOC-2982

Regards,

Patrick

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Hi Patrick,

Excuse me for being late but i have preferred test the system for long time.

i confirm the problems are only in SPA942 Phone not in cordless connect in FXS2 od SPA9000.

after reset the system (switch included) the line are ok for 1 or 2 days after this, the line have "walkie talkie" effects with more pause (like silence suppression active but now are not active) and more word are lost in conversetion. Audio are volume more low to the remote caller but if I approach my microphone to my mouth, I feel their best.

i attach config of my system

thanks for support

Thomas

Hi Thomas,

Thanks for the configuration files. Please don't forget to send me an audio recording of the audio problems and sounds.

Regards,

Patrick

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Hi Thomas,

Can you test with a different switch please? The switch is a common device that could affect the attached phones.

Please confirm does the SPA941 have this problem, or is it only SPA942 phones?

Regards,

Patrick

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