B5.5 1.8T burning smell

[stomper]

I've noticed a burning smell over the last few weeks which has been getting worse. The car's not using any oil. You can smell it when stationery but not driving along.

Checked under bonnet after a long run the other day and there are deposits on the exhaust to the left of the engine as you look at it and there was smoke coming off it.

Been reading up on a few forums for similar symptoms and the following were mentioned:

Blocked PCV, Cam cover, Valve cover.

Do these sound possible causes?

Thanks in advance