audio_CrasLoopback is failing intermittently on boards like elm, veyron_jerry, asuka, banon, butterfly, cave, nyan_big, peach_pit, squawks, and stout.

The error is "Timeout waiting active stream count to become 0".

    cras_utils.capture(noise_file, duration=1)
    self.wait_for_active_stream_count(0)


I reproduced the issue on elm. cras_test_client capturing worked fine. The problem was there was another active stream while testing. That active stream is never closed. Jimmy. Is that expected?

# cras_test_client --dump_s
System Volume (0-100): 100 
Capture Gain (0.00 - 0.00): 0.00dB 
User muted: Not muted
Output Devices:
	ID	Name
	8	mtk-rt5650: :0,2
	6	mtk-rt5650: :0,0
Output Nodes:
	Stable Id	 ID	 Vol   Plugged	L/R swapped	      Time Hotword	Type		 Name
	(1853bfca)	8:0	  100       no	            no	         0        	HDMI             mtk-rt5650 HDMI Jack
	(9e934263)	6:0	  100      yes	            no	1508549600        	HEADPHONE       *Headphone
	(72a57953)	6:1	  100      yes	            no	1508549600        	INTERNAL_SPEAKER Speaker
Input Devices:
	ID	Name
	7	mtk-rt5650: :0,1
	5	Post DSP Loopback
	4	Post Mix Pre DSP Loopback
Input Nodes:
	Stable Id	 ID	Gain   Plugged	L/R swapped	      Time Hotword	Type		 Name
	(1d13c3f3)	7:0	    0      yes	            no	1508549601        	MIC             *Mic
	(30b0c661)	7:1	    0      yes	            no	1508549601        	INTERNAL_MIC     Internal Mic
	(8c74f766)	5:0	    0      yes	            no	         0        	POST_DSP_LOOPBACK Post DSP Loopback
	(8a04af91)	4:0	    0      yes	            no	         0        	POST_MIX_LOOPBACK Post Mix Pre DSP Loopback
Attached clients:
	ID	pid	uid
	10	23884	0
	11	23884	0
	22	26101	0
Num active streams: 1
Last audio active time: 1304, 101445534