Hello,
I have tested this on our internal (all latest version) PBX and have no issues/errors, but on a new install I get the following error:
Undefined variable: prefix
File:/var/www/html/admin/modules/endpoint/functions.inc/functions_common.php:2730
I am adding for a Cisco SPA phone a default ring tone.
After setting the values as follow, I get the error when I click apply & update.
HOWEVER, if I only click save, I do NOT get the error.
File: spa
UA: Ext_1/Call_Feature_Settings
Parameter: Default_Ring__1__ group
Value: 10