== == Could be a pebble stuck in the tread of one of your tires.The ticking noise only appears to disappear because the tone or pitch of the noise gets higher with speed to the point at which it is undetectable to the human ear.
The ticking noise is the metal cooling.
The fuel injectors make the ticking noise you hear at startup, especially when the engine is cold (colder temperatures).
there is a rattling noise in the area of the serpentine bell
If you are loading a Cd-rom,or a program.
well it sounds like your lifters are ticking The connecting rods screaming LET ME OUT!!!
horses make neighing sounds
you may have a bent valve
98 Chevy new 383 block 30k, ticking noise from sounds like heads . 210k on heads;
Its not your brakes making the noise. Most liklly your CV joint is warn out.
Well if its sort of like a scratchy noise coming from the engine you might want to get your transmission checked out
Without the year, make or model of your vehicle it could be a bad compressor and or a bad compressor clutch.............
If your vehicle has a timing belt and not a chain, you need to replace it immediately. My distributor made the same ticking noise and it turned out to be the timing belt had a frayed piece on it and this piece was the source of the noise. Before I could figure it out, the belt broke and left me stranded on the roadside.