we are using CUCM 6.1.4. Calls to other SIP phones and to the PSTN are fine. Calls to SCCP 7975s sound like they are overdriven. Codecs should be g.711. Has anyone heard of similar issues? I don't think callmanager has anything to do with this, but want to see if this is a known issue. This is my first experience with 3rd party SIP phones.