Have the Nexus get 6 32GB Blue yesterday (was indeed longer unavailable). However, I had to read just as it did in other reviews I have this noise / scratching the top speaker. Stark during a conversation and as well as system sounds or as YouTube videos look. At low battery level, the noise is becoming stronger. Today I led a replacement and hope that does not have the new problem. As I said without this problem it would be a top phone for me.
Addendum:
Replacement mobile phone has come today, unfortunately, with the same symptoms as that first. That's it then back to the Nexus 6. It is. In a 600 phone such quality defects should not occur.