When multiple calls (mostly 3 calls) come in to a response group and phones are not being answered, phones start to ring louder and louder.

We have CX600 Polycom phones tethered to a computer.

Anybody ran into this behavior before and know how to fix this?

Hi,

The distinct tone is sequentially played once at maximum volume. The peak decibel value for each version was reached in the default Ringtone 5 setting, but it was only increased by roughly 3dB.  Notice that all other ringtones appear to indicate a larger increase by comparison, for example Ringtone 1 which shows nearly a 10db gain.

However, a sound heard at 90dB is perceived as twice as loud as a sound heard at 80dB.

More details:

http://blog.schertz.name/2012/05/new-lync-phone-edition-features/

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From the link below, it is by design by Polycom side. So you can contact Polycom side, and ask if there is any workaround for this issue. Thanks for your understanding.

Best Regards,
Eason Huang