Anybody Know about Gas Fires?

We've got a coal fire effect gas fire (it's called a Panache Plus 6 for what it's worth). It's about 8 years sold.

Anyway, when we turn on the main flame it seems to take all the oomph out of the pilot light which no longer reaches the thermocouple jobby and the whole thing goes out.

I've given it a good clean externally and poked stuff into the pilot light hole to make sure it isn't blocked to no avail.

Any ideas please?

Ta
"Reg"