I have a site with 7920 model IP phones and from a full charged battery, if you leave the phone on a desk (not plugged in) just sitting there registered, the battery is empty in about 3 hours. The phones are configured to use 128 bit WPA encryption. The phoneload version is cmterm_7920.4.0-03-02.
I have taken another 7920 out there, and it does the same thing. I have taken my spare 7920 back with me, and it has been 7 hours since I left the site and the phone was full battery when I left and now has a little over one third battery left and has been sitting here trying to authenticate and saids No network now and then, but the battery is still alive 7 hrs later. Yet, at the site it was full and died within 3 hrs when the phone was authenticated and registered to CME and idle except for the 1 or 2 calls I made.
I have not plugged it into a charger for the past 7 hours.
Could the encryption type configured have a impact on the battery life by this much?
This is quite puzzling.