No sound on Dell 3910 (Win)

Deskmargin: 0;">External sound card: Creative Audigy FX

Since W11 update 2024H2 I hear sound with crackling when playing videos and music, when I send the 3.5 mm jack from the external sound card to the amplifier. However, if I set the default output device to the mini speakers of my AOC screen via Settings / Sound, the sound can be heard without crackling.

If I remove the External sound card and connect the 3.5mm jack to the audio output (audio-on-board) on the desktop, there is no sound at all.