I have a UC320W router and SPA504G phones. We just added our 4th analog phone line and connected it to the 4th FXO port on the UC320W. When I try to add the 4th FXO line to the list of Shared Lines I'm unable to have it show up as the 4th line / 4th button on the SPA504G phones. The error states 'Not enough buttons'. Wondering how I can get rid of the personal Extension button and use all 4 buttons of the SPA504G phones for each of my 4 lines.
Any help would be much appreciated. I've poured through the router and phone manuals and can't find any info on how to achieve this. Thanks in advance.