attend , your codec_dump (HP ProDesk 400 G5 MT) is identical to the codec_dump of the (HP ProDesk 600 G3 MT). The audio codec is the same. Swapping LineOut back and internal speaker was intentional for SwitchMode.
LayoutID15: SwitchMode LineOut back (as internal speaker) with headphone front.
LayoutID16: SwitchMode internal speaker with headphone front. LineOut back extra as LineOut.
Input's changed again. Try front Mic now. Also try with pre-amplified mic or the headphone trial.