This looks like the same problem I've had. I spent two days stripping the code down to almost nothing to prove it as the failure occurred in a completely different area.
I've now replaced one of the 'select cases' with 'if thens' and it works. This leaves ten select cases so the problem looks like something in compilation.
Whilst looking for the problem I put a lot on 'availableRAM' checks in the code and noticed that the figure increased from 136 to 4294967257 at about the same time as the failure, though again in a different part of the code. That's clearly not feasible on a Uno!! But I don't know if it's related to this problem of something else I need to look for.
Anyone have any suggestions re. the select/ case problem? (or memory figure for that matter)