ian, you can send email to sonosax [at] sonsax [dot] ch (note that last part--ch for Switzerland) and explain the problem to them. They understand English there, and they write English well enough to give you the advice you need.
The SX-M2 is made with mostly surface-mount components. Many--perhaps most--repair shops and technicians aren't equipped to deal with that technology, although they may still tell you, "Sure, we can fix it." And then they have to hope to get out of the situation somehow without a huge mess.
Half the time they can do so, since half the time there's nothing really wrong with what the customer brought in in the first place--instead it's cables, some component other than the one that was brought in, a connector that needed cleaning, or an RTFM problem. And the other half of the time, they either luck out (maybe it's a non-surface-mount part which they can replace) or as a last resort, just confuse or intimidate the customer.
If I seem to have a cynical attitude about repair shops, it's because I used to work in one. It was one of the best around, but games were still played with the customers on a daily basis. One of the long-time techs used to put his phone on speakerphone, and the others would gather around as he bullshat customers. It was a bit like "Liar's Poker."
After a few weeks there I did the math and figured out that without playing such games, I was earning very close to minimum wage. Since then I have understood what makes things be the way they are. But the fact that I know many of the dodges and ruses doesn't protect me when something of mine is broken that I can't fix myself. So I have a decided preference for manufacturer's service rather than third-party service--or third-party service only from people who I'm friends with and trust personally.
This is not meant as any kind of comment on the companies mentioned earlier in this thread; I haven't dealt with them, and don't know what they're made of. But with critical, high-quality equipment (especially something so highly miniaturized) I would always rather go where the manufacturer tells me to go with it, unless I had a pretty near unanimous user community telling me otherwise.
--best regards