No audio on 3.5mm jack after update to kernel 6.18 (current)

[Manuel R]

Hi all,
 

After a recent update bumped the current kernel to the 6.18 series, the rear 3.5mm jack on my NanoPC-T6 LTS stopped playing any sound. I'm connecting it to an external amplifier that worked fine before the update.
 

What I see on 6.18 (6.18.35-current-rockchip64):

 

• The audio card (rt5616) still shows up in aplay -l and playback commands run without errors, but no sound comes out.
• Volume levels and mute aren't the issue — I checked those.

What fixed it: downgrading via armbian-config to linux-image-current-rockchip64=25.11.2 (kernel 6.12.58). With 6.12 the audio works perfectly again.

So 6.12 works and 6.18 doesn't, at least on my board. Is anyone else seeing this on a T6 / T6 LTS with the 6.18 current kernel? Happy to share any logs or run commands if it helps to narrow it down.

Thanks!