I've been looking around and so far had no luck finding an 8.1 bug for MOH.
I've got a customer with a UC560 that is unable to get the external MOH jack working. I tested it myself from my blackberry so I know the music source is good. I've changed the setting under features in CCA to external music source and tested the hold music with both internal and external calling and all I get is this awful tone.
On a side note: I've scheduled an upgrade to 8.2 next week anyways because they need the extra licensing for additional sets.
Just an FYI in case anyone else is having the same issue. Upgraded to 8.2 and everything all of a sudden works just fine. I did not make any programming changes from 8.1 to 8.2 just the upgrade resolved the issue.
Configure Multicast Paging on the Cisco IP Phone 7800 Series or 8800 Series Multiplatform Phone
The Cisco IP Phone 7800 and 8800 Series Multiplatform Phones provide voice communication over an Internet Protocol (IP) network...
Add Call Park on a Cisco 7800 or 8800 Series Multiplatform Phone Key Expansion Module
Call park allows the user of the phone to put an incoming call on hold so that the call can be retrieved on another phone. A call is park...