Apple sent an empty box back to me - anyone had this experience?

Hey Everyone!

So Apple sent my repair item back but I received an empty box! Anyone else have this experience? and if so what did you do to resolve?

My story goes like this:

• my powerbeats worked perfectly except sometime the left bud intermittently charged / didn't connect
• Sent my Powerbeats in for repair and the left bud intermittently charged, despite being a well known design flaw, apple say it's due to 'corrosion' so I opt for my item to be returned
• I receive the item back except now the buds don't connect together (either one or the other connects but not both) despite following all tech support on resetting the issue never gets better - I'm advised to go to a store
• Go to a store who tell me they can't see any damage and that if the repair team were to say it was damaged again then I'll be covered under consumer law (all confirmed via email), I clearly state all I want is for the powerbeats to connect properly as they did before I sent them for repair. store takes my powerbeats and sends them for repair.
• Repair team come back and say issue is corrosion. So I call Apple Support, Apple Support / Apple Care so it's not their issue and I have to talk to the store. Even more so, I have to wait for the item to come back to me before I can do anything.
• DPD parcel arrives (girlfriend collects it from the delivery driver and puts on kitchen counter).
• I call the store who tell me they can't help and that I need to speak to Apple Care (who tell me I need to speak to the store) Store informs me despite originally stating that they could not see any damage and that I was covered by consumer law , that the repair team have the final say and in that case it doesn't matter what the store say. (i.e. what I have in writing means nothing)
• Later in the day I go to open the DPD package, as soon as I pick it up I can feel it's too light and when I open the package there is an advice note and box but nothing in the box!

Anyone else have this happen to you? What was your resolution? Not sure if I should be surprised by the poor customer service or not!