similar problem: Replacing a toshiba VI with a toshiba XII. Customer wanted more lines, went to ElCheapo phone dealer, then called us when the used crap wouldn't work.
Programming phone is an EK, not DK.
Customer is using DK2010 non-display phones for users. System has been defaulted to square set-up (all lines on all phones). Lines appear on appropriate buttons, lights flash when called, but no audible ringing.
Checked volume sliders on phones, checked program 81xx, system is in day mode, good dialtone for outbound, otherwise fine.
Also, customer wants to be able to use headsets without going off-hook. Original vendor has installed internal card with additional jack for headset. As nearly as I can tell, these are installed correctly and connected correctly - white loop of wire is cut - but you must lift the handset to use the headset.
Any wisdom on this problem? (Aside from, "don't accept work passed off from JackA$$ Telecom vendors?")
