ringback errors when parking calls hud 2

http://fonality.com/trixbox/forums/trixbox-pro/trixbox-pro-help/r...

i found the link above when researching this issue for a customer. They can place calls in Call Parking in HUD but then they disappear. They can pick it up by dialing the extension the call was parked on but not from HUD. I have checked permissons and all seems fine there. Below is CLI output from my test.

Executing ParkAndAnnounce("Zap/6-1", "|600|/dev/null|internal|1010|1") in new stack
-- Dial Tech,String: (,dev/null)
-- Return Context: (internal,1010,1) ID: my phone number
-- Started music on hold, class 'default', on channel 'Zap/6-1'
== Parked Zap/6-1 on 9001. Will timeout back to extension [internal] 1010, 1 in 600 seconds
-- Added extension '9001' priority 1 to parkedcalls
-- Call Parking Called, lot: 9001, timeout: 600000, context: internal
Jan 13 14:58:57 WARNING[32363]: channel.c:2918 ast_request: No channel type registered for ''
Jan 13 14:58:57 NOTICE[32363]: channel.c:2787 __ast_request_and_dial: Unable to request channel /dev/null
Jan 13 14:58:57 WARNING[32363]: app_parkandannounce.c:202 parkandannounce_exec: PARK: Unable to allocate announce channel.
== Spawn extension (internal, 1010, 1) exited non-zero on 'Parked/Zap/6-1'
-- Executing ResetCDR("Parked/Zap/6-1", "w") in new stack
-- Executing NoCDR("Parked/Zap/6-1", "") in new stack
Jan 13 14:58:57 NOTICE[32363]: cdr.c:445 ast_cdr_free: CDR on channel 'Zap/6-1' lacks end
-- Executing GotoIf("Parked/Zap/6-1", "1?5") in new stack
-- Goto (internal,h,5)
-- Executing Hangup("Parked/Zap/6-1", "") in new stack
== Spawn extension (internal, h, 5) exited non-zero on 'Parked/Zap/6-1'
-- Stopped music on hold on Zap/6-1
-- Started music on hold, class 'default', on channel 'Zap/6-1'
-- Stopped music on hold on Zap/6-1
-- Started music on hold, class 'default', on channel 'Zap/6-1'
-- Stopped music on hold on Zap/6-1
-- Started music on hold, class 'default', on channel 'Zap/6-1'
-- Stopped music on hold on Zap/6-1