Hi!
I understand that you have audio issues only when your laptop is plugged into power.
Please try the steps recommended below.
In Windows, type sounds into Search. Select Change system sounds in the Search results.
Alternatively, right-click the speaker icon on the taskbar and select Playback devices.
In the Sound window, from the Playback tab, select your playback device, then click Set Default. If only one playback device is listed, it is set to default automatically.
If you set speakers as your default device, proceed to the next step.
With the default playback device selected, click Configure.
Click your speaker setup in Audio channels.
Click Test to send sound to each speaker, or select an individual speaker to send sound to that speaker.
If the sound is heard correctly from each speaker, you are finished.
If the sound is missing from all or one of the speakers, or if the configuration type was changed, continue with speaker setup by clicking Next. Follow the onscreen instructions to complete the speaker setup.
Refer this article to further troubleshoot audio issues.
Have you tried checking with a different adapter?
Let me know how it goes!
Have a great day!