Strange noise

Finally got the D4 back from the dealer today.
They replaced the HP fuel pump under extended warranty which appears to have fixed the "chirp" at an estimated $3000 warranty cost.
They also found a leaking EGR gasket that was leaking exhaust straight into the HP fuel pump area making a mess everywhere.
Unfortunately this required a "body off" to locate and replace the gasket, delaying the job further as all the front and rear aftermarket bars etc had to be removed.
I will give it a good run over the next day or two and hopefully that's the last of the "chirp".
It pays to trust your gut and get noises checked out to your satisfaction.