i have CCM 4.1, Unity 4.0(5), 7960's, 7970's, and 7912G's ip phones, whenever i login to the voice mail the 7912 ONLY hears a very noisy sound like drilling voice, but if i look at the call monitor status it shows that its playing the greeting. the ccm, unity and all phones are running 711mulaw. i suspected that in a way or another that 7912 only can't understand the codec of the unity???
The minimum OS version for CCM 4.1(3) was 2000.2.6. So you should be OK. I don't think the OS version would affect the voice quality of your 7912G phones. Have you posted this question on the IP Telephony forum yet? You may get better/more responses. When I posted our earlier phone load version for the 7912G, I forgot to mention we are only Skinny at this time (SCCP), not SIP.
The 7912 default load for our CCM 4.1(3) is CP7912060101SCCP050429B. Also, you might be able to run the Quality Reporting Tool to get some data of value for you and/or TAC - here is a link to the troubleshooting guide for the 7912 -
SIP traces provide key information in troubleshooting SIP Trunks, SIP
endpoints and other SIP related issues. Even though these traces are in
clear text, these texts can be gibberish unless you understand fully
what they mean. This document attempts to br...
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partners have asked for more in-depth training in being able to properly
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