No sound from speakers after replacing 3.0 Ghz logic board with 3.4 G in 2017 21.5 iMac

Everything else works great, and I’m sure I connected the speaker cable properly when re-assembling the computer after installing the new logic board. The Audio specs showing in system settings read as follows:

Devices:

Built-in Microphone:

     Default Input Device: Yes 

     Input Channels: 2

     Manufacturer: Apple Inc.

     Current SampleRate: 44100

     Transport: Built-in

     Input Source: Internal Microphone

Built-in Output:

     Default Output Device: Yes

     Default System Output Device: Yes

     Manufacturer: Apple Inc.

     Output Channels: 2

     Current SampleRate: 44100

     Transport: Built-in

     Output Source: Headphones

Microsoft Teams Audio:

     Input Channels: 2

     Manufacturer: Microsoft Corp.

     Output Channels: 2

     Current SampleRate: 48000

     Transport: Virtual

     Input Source: Microsoft Teams Audio Device

     Output Source: Microsoft Teams Audio Device

Am I missing a hardware device or do I need to install upgraded/newer firmware or sound device drivers? If so, how do I do that?

[Re-Titled by Moderator]