I have had an unusual amount of failures on some cp-7941G sets. The Hook switch starts to not function properly after a short time (couple of months). I have had three in just the last week. These phones were located in either a warehouse or guard shacks. We have also experienced this problem at another site near an indoor pool. We thought it might be humidity related. TAC says they have had no reports of this. We took one apart and tinkered with the hook switch this corrected the issue but only for a few days. Has anyone else seen this type of issue?