Exhaust ticking and not sealing!

Hello All
I have searched (ticking) and I realise I may have a potential Exhaust manifold gasket to change...but before I do, can I ask would I get the exhaust ticking sound from a leaky exhaust downpipe off the manifold/turbo elbow.
I have replaced with a correct clamp, but the down pipe will just not tighted up enough! when I blip the throttle I can see exhaust gas come from the joint.
What would you reccomend to use as sealant? Should I drop the downpipe off again and cover the elbow with some type of high temp sealant before delving into removing and changing the manifold gasket?

Silicone sealer. I replaced the exhaust on my s4 recently fitting a full stainless system. First time I used exhaust paste that drys hard and it started blowing after a few days. Then I pulled it all apart again and used silicone sealer that works to high temp. never had any problems since doing this in sept. Better for assembly too.

holts fire gum

thanks for the advise guys

Ok, its deffo the gasket thats gone on the rear end! I am going to follow Busters guide, but can I ask a Newbie question please....Buster cleans the head before replacing the gasket...Whats the tried and tested best way to do this please? Also I presume I would want to put some rags inside the inlet and exhaust bores to stop crap from falling in? Any tips please, should I use a mild cleaning pad on a drill bit etc?
Thanks as always in advance
Sean

Wire brush,hand or power works well on old gasket, like you say plug all holes.