When you dial into a voice tree and make a selection to go to the next level, you are sometimes dropped all together. On the channel monitor, there are still plenty of available channels. This only happens in 1 of 20 calls but it is not a once a month problem that I can pass off as "well, it happens". When we actually sat down to try to find the problem, it works fine (cruel irony). Of course the problem is at it's worst when the boss is glaring at you over your shoulder. Any ideas on how to remedy or even track this problem.