Pioneer VM-50 completely silent but still wakes from standby. Is this something we can DIY?

[u/Due-Yesterday5208]

My girlfriend has a single Pioneer DJ VM-50 that she runs off her DDJ-REV7. It suddenly stopped producing any sound at all.

The power LED still behaves normally:
It goes red when it drops into auto-standby
It switches back to white when the REV7 wakes up or a track plays.

So it seems to detect the signal and power on, but nothing comes out of either driver.
What we've ruled out:

No hiss at all, even with the volume knob maxed and an ear right against both the woofer and tweeter

The REV7 works fine through headphones

Tried different REV7 outputs, with Master and Booth levels up

Swapped cable ends and wiggled the connections at both ends. No crackle, no sound.
Checked the volume and the settings on the back of the speaker

A shop quoted $300 to fix it, which is close to the cost of a new one.

Honestly, we're pretty new to this and don't really know how to go about diagnosing it. We're both pretty handy with this kind of thing though, so we'd love to try fixing it ourselves if it's realistic. Is this something we could DIY? Any pointers on where to start would be hugely appreciated.

Thanks in advance!

[u/Dry-Satisfaction-633]

It’s the usual repair conundrum - if you have to ask if you can fix it the answer is probably no, otherwise you would already be busy fixing it. Did you know it’s possible to get more than one repair quote? $300 is steep and it’s unlikely the material or labour costs will be anywhere near that. It sounds more like the shop is going through a fallow patch and they’re using your misfortune and lack of knowledge to help keep the lights on. Get another quote from someone who’s honest enough to tell you it’s uneconomical to repair (if that truly is the case) rather than offer to fix it for the same cost as replacement. If they’re honest enough to do that they’re likely honest enough to give a fair quote for what actually needs doing rather than some high, cover-all quote that doesn’t reflect what was replaced or how long it took.