(Figure 1 - Volume icon still displays X)
This is an Audio Driver coding issue.
Go to check the audio codec device ID to identify the audio vendor in Device Manager.
Cirrus Logic High Definition Audio: VEN_1013&DEV_8409 (See Figure.2)
(Figure 2 - VEN_1013&DEV_8409)
Updating the Intel Cirrus Logic High Definition Audio Driver to Version 10.0.6.5 or later on the computer resolves the issue. To download and install the driver, reference How to Download and Install Dell Drivers.
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