Maybe it's more noticeable because this phone has a really tiny battery, but yeah.

I actually went through a few adapters to find one that worked, because some of them (e.g. the one Apple makes) actually only wire up a DAC inside the phone to the physical 3.5mm connector. The Palm phone doesn't have a DAC though ...

Maybe the one I have (by a company called Baseus, which I've never heard of before) just sucks and it shouldn't be drawing as much power as it does. Thanks for the link to that video, might be some good alternative in there!

The 3.5mm adapters that Apple makes absolutely include a DAC themselves. Not sure where you get the idea that they don't.

Both the USB-C and the Lightning versions are all digital on the port side.

There are very few USB-C analog -> 3.5mm adapters, strictly because there is so many compatible issues (i.e., you need to support the alternate mode, AND you need to map the pins correctly).

There’s a real DAC inside the Apple one: https://www.ifixit.com/Teardown/Apple+Lightning+to+Headphone...

I got an official Apple one and couldn't get it to work with any of my devices (I don't have any other Apple devices, so maybe they do have a DAC but it only works with their devices?). It exhibited the same behaviour as the DAC-less adapters (i.e. just, well, nothing).