Lets not get crazy here and think everyone with a liquid shifting sound has a warped cylinder head!
Check your radiator and overflow to see if its the coolant is topped off, it might just be an air bubble, it can be hard get those to bleed out all the way, haven't really looked but wherever the highest part of the cooling system is, if there's a bleeder, crack it open slightly and watch the air pop out.
When your adding coolant allow the vehicle to come up to temp (Thermostat will open) and have your heat on full/full, then ac on full/full. Close it all up prior to that wonderfull boil over event and turn off the vehicle. Take it for a drive and don't be afraid to rev it up some to get that waterpump pumping.
Thats my usual cycle to make sure I get the air out of my vehicles.
However, its under warranty and the dealer will do all of the above for you
should you air issues.
Is this a 1.8L or 1.4 Turbo? I ask because I did notice my 1.8L seems to vibrate pretty good at idle (not enough to give feedback in the car/steering wheel) when I watch it with the hood popped. Does pull strong so I now its not down on power.