The version of BE6K is 10.X , The vesion of CUCM is 10.5.X ,the desktop client voice sounds low, between mobile devices such as IPHONE ,sound is normal.
Please tell me what are the options can adjust.
I recommend you also post this to the Cisco Support Community for additional feedback and information.
Cisco Support Community
Hope this helps.
Moderator for Cisco Customer Communities
i resolve the problem
because lic is trial.
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