ALSA dsnoop causes issue with GStreamer video

[StreaminBaby]

Hello there, 

I am using GStreamer to stream live video / audio from a Pi3B with a picam
module and USB microphone. My end goal is to use the audio from the one USB
microphone in both the live video / audio stream AND as the input to a
python script. I understand that this can be done with the ALSA dsnoop
plugin and have been able to demonstrate it with this /etc/asound.conf
config:

    pcm.myTest {
        type dsnoop
        ipc_key 2241234
        slave {
            pcm "hw:1,0"
            channels 1
        }
    }

    pcm.!default {
            type asym
            playback.pcm {
                    type plug
                    slave.pcm "hw:0,0"
            }
            capture.pcm {
                    type plug
                    slave.pcm "myTest"
            }
    }

With the above ALSA config, the video / audio stream works perfectly using
the following GStreamer settings, but i am unable to use the microphone in
other applications (note the "hw:1,0"):

    #!/bin/bash
    gst-launch-1.0 -v rpicamsrc vflip=true hflip=false \
                   name=src preview=0 fullscreen=0 bitrate=10000000 \
                   annotation-mode=time annotation-text-size=20 \
                   ! video/x-h264,width=960,height=540,framerate=24/1 \
                   ! h264parse \
                   ! rtph264pay config-interval=1 pt=96 \
                   ! queue max-size-bytes=0 max-size-buffers=0 \
                   ! udpsink host=192.168.1.101 port=5001 \
                   alsasrc device=hw:1,0 \
                   ! audioconvert \
                   ! audioresample \
                   ! opusenc \
                   ! rtpopuspay \
                   ! queue max-size-bytes=0 max-size-buffers=0 \
                   ! udpsink host=192.168.1.101 port=5002


The following (which uses the dsnoop device) causes an issue in the video
stream which looks like some kind of synchronization problem where instead
of a nice smooth 24 frames per second I get one frame every ~2-3 seconds.
The audio continues to work well and im able to use the USB mic
simultaneously in other applications.

    #!/bin/bash
    gst-launch-1.0 -v rpicamsrc vflip=true hflip=false \
                   name=src preview=0 fullscreen=0 bitrate=10000000 \
                   annotation-mode=time annotation-text-size=20 \
                   ! video/x-h264,width=960,height=540,framerate=24/1 \
                   ! h264parse \
                   ! rtph264pay config-interval=1 pt=96 \
                   ! queue max-size-bytes=0 max-size-buffers=0 \
                   ! udpsink host=192.168.1.101 port=5001 \
                   alsasrc device=plug:myTest \
                   ! audioconvert \
                   ! audioresample \
                   ! opusenc \
                   ! rtpopuspay \
                   ! queue max-size-bytes=0 max-size-buffers=0 \
                   ! udpsink host=192.168.1.101 port=5002

I've tried a few things that I've found in some peripherally related forums
to no avail and im feeling kinda stuck. Do any of you have any suggestions
on getting the stream's video to play nicely with dsnoop so that I can avoid
buying another microphone for this project? 

Thank you for what you do!



--
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