Is there a limit on how many LCOT4 cards can be installed on the NCP1000? I have slot 4 free currently. Slots 1 and 3 have an LCOT4 in them and Slot 2 has a DHLC4 card in it. I cannot find anything in documentation that says I cannot put an LCOT4 card in slot 4, but thought I would check here. Customer would like to add 2 additional lines for outbound calling, but current ports are full.