The DTMFDispatcher thread of the DtmfTransformEngine is not stopped when the DtmfTransformEngine is closed

[konikb]

Description

An AudioMediaStream is created with a DTMFListener (the stream is established between a server application based on libjitsi and a SIP phone). Receiving a RTP DTMF tone (RFC4733) from the phone leads to the DTMFDispatcher thread creation in the DtmfTransformEngine. But when the media stream is closed the DTMFDispatcher thread remains.

Expected Behavior

The thread should be stopped.

Possible Solution

I think that stop() should be invoked in the close() method of the DtmfTransformEngine, or dtmfTransformEngine.stop() should be invoked in the AudiMediaStreamImpl close() method.