Yes you have to install a service card for clocking,no programming is needed just install it in slot 2.are you using the built in CSU or you using outside CSU,if you using the internal one make sure its turn on,if not you can loose calls and sync.

BY the way is this the same system you having a problem with call park and dropping calls,if its what is the s/w version ,there were alot of issues like what you descriping in the early version of 3.0 and 4.o

Good Luck.