Hello,
I'm not a Comdial guy...but I was at a customers site who has a Impact 816 and at ext. 10 the hold button is constantly flashing... and on the display it says something along the lines of "call ext. 10"..
Any suggestions..I remember coming across some of the old executechs that had this problem...I think it's cause by the customer inadvertently pressing a key combination causing to go on... I know you can turn on some features by doing -intercom * # ..etc..