Not knowing the exact details of the device you are querying or the software version on it, it's difficult to comment on your exact system - but, if you are running a recent software release on your device, there is an option to change the function of the internal speaker. See the "Audio Output InternalSpeaker Mode" setting.
Audio Output InternalSpeaker Mode
Define whether or not to use the device's integrated speakers. You can limit their use to
play only ultrasound.
Requires user role: ADMIN, INTEGRATOR
Default value: On
Value space: Off/On/UltrasoundOnly
Off: Disable the device's integrated speakers.
On: Enable the device's integrated speakers.
UltrasoundOnly: Enable the device's integrated speakers only for ultrasound
Wayne
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