Can the MKRZERO record WAV audio to the onboard SD?

I've seen countless posts on recording audio (both electret & MEMS), writing WAV files, specifying custom interrupt timers, and optimising writing to SD cards. I've seen articles about recording audio to SD on other Arduino boards (not the SAMD21 chips). But try as I might, the closest I get is awful, noisy, faint audio...

...is this actually possible?! On paper the MKRZERO seems perfectly capable and I assume it is my inexperience that is the limiting factor, but I thought I'd ask.

Sounds like an impedance match problem on the audio source. Try synthesizing the digital audio in Arduino software and also try looking at the digital data you are getting from your A-to-D. Of course it could be a bad audio cable, that can ruin your whole day.

Thanks for the reply, SurfingDude - I will certainly look into those.

But does anyone know it works? Has anyone successful captured and saved half decent audio?