Problem: Batch of phones that have an abnormal amount of hookswitch problems. The phones do not recognize the handset has been removed from the cradle. The only way to answer/place calls is to use the speaker function.
I have followed the cleaning procedure as recommended in Doc ID 45283, "Best Practices for Cleaning and Troubleshooting Cisco IP Phone Hookswitch". This does not work.
There are 1120 phones in the cluster and at this one site of 100 phones, probably 10% have failed with this problem. The only known solution has been to replace the phones at this time.
Does anyone have any suggestions or recommendations other than the 45283 document?