Active outgoing voice call "stuck"

Active outgoing voice call "stuck"

This article provides information for users experiencing that phone calls from TopView not progressing.  
Versions affected: 7.2 and earlier
Patch: available for v7.2 on the TopView 7.2 download page

Symptoms
  1. Outgoing calls are not being received
  2. Incoming calls may not be answered
  3. TopView Admin Tools:
    1. Viewing of the outgoing call queue: calls are in the queue but calls are not being completed and removed from the queue  
    2. Viewing of most recent outgoing call log, the last message is "Getting softphone (Recipient=...)"
  4. TopView 7.2: an Engine health warning is displayed:
    "Voice notification queue has not been processed for ... minutes - check queue and most recent notification log"
Background
A softphone is a software-based VoIP phone client used to make/receive calls and for SIP IM. Each softphone usage in TopView is implemented using a separate softphone. Usage can include outgoing call primary/failover, incoming call, and SIP IM primary/failover.
The management of TopView softphones is controlled by an internal softphone factory. Before a new outgoing call is made, TopView asks the softphone factory for the current softphone (primary/failover). Other uses of softphones will also make requests to the factory for the current softphone.
Outgoing calls in TopView are placed into a queue. TopView determines which call to make next, gets the correct softphone from the factory, makes the call, and then removes the call from the queue.

Issue
It is possible that a call into the factory does not return the phone. Instead, the factory is "locked" and callers into the factory are waiting for the factory to return the phone. These locked requests are running on background threads, so although the TopView Engine continues to run, the tasks associated with the locked factory calls are stuck. The end result is that softphone related tasks are no longer executing.

Fix
A patch is available for TopView 7.2 on the TopView 7.2 download page.
Users of earlier versions of TopView will need to upgrade to v7.2 to apply the patch or install a version later than 7.2