Ticking noise V8i when warm

My 98 Disco v8 has started to make a ticking noise but only when warm.
I can't tell if it's coming from the engine or the exhaust / cat area. It increases / decreases with revs but is only really noticeable at tickover.

Engine runs fine its just a noise and only when fully warmed up. Oil changed 3000 miles ago.

Any idea??

Could be a manifold gasket.....mine did something similar which i cured by replacing the gasket.

Look in the V8 section, there's a similar thread.

twas the O/S manifold gasket wiv mine, sorted now.