Installed a TDA100 with a TVA50 back in 2009. Just started having problems on CO lines 1 and 2 were the buttons on the phones are lit red as if someone is using the line but nobody is. Its like the line is stuck and wont clear so you can use it. Very random too. Only has happened 4 times in the last 3 weeks. I went around and unplugged each phone and plugged it back in to see if it was a bad phone but the light stayed red through that whole process. The only way I could clear the light is to shut down the system and turn it back on.
They are using an LCOT16 card.
Any ideas on why a line gets stuck like that and happening very random and not all the time??
Thanks