I've seen reference to this problem before, but I haven't seen a solution. When I enable Audio Alerts within Attendant Console, I only hear the first quarter second of the audio, whether it's the standard audio file or one that I put in there. Also, for the New Call audio, if I disconnect the call before answering, I do hear a little noise on the computer, like the computer was actually playing a audio file of silence and stopped abruptly. I've heard that this works for other people, so I suspect it might be a sound card problem, but all other sound on my computer works fine.
I am using CUCM 6.1.3 and Attendant Console server and client 6.1.1_c.