Piping? I haven't heard this. Help me understand what piping is and how/when are you likely to experience it?
Here's an audio clip http://hemingwaysouthcarolina.com/sounds/queenpiping.wav
Piping describes a noise made by virgin and mated queen bees during certain times of the virgin queens development. Fully developed virgin queens communicate through vibratory signals: "quacking" from virgin queens in their queen cells and "tooting" from queens free in the colony, collectively known as piping. A virgin queen may frequently pipe before she emerges from her cell and for a brief time afterwards. Mated queens may briefly pipe after being released in a hive. The piping sound is variously described as a children's trumpet tooting and quacking. It is quite loud and can be clearly heard outside the hive. The piping sound is created by the flight motor without movement of the wings. The vibration energy is resonated by the thorax.
Piping is most common when there is more than one queen in a hive. It is postulated that the piping is a form of battle cry announcing to competing queens and the workers their willingness to fight. It may also be a signal to the worker bees which queen is the most worthwhile to support.
The piping sound is a G♯ or A♮. The adult queen pipes for a two-second pulse followed by a series of quarter-second toots. The queens of Africanized bees produce more vigorous and frequent bouts of piping.
I copy and pasted the above for you, hope this helps.