Play recording while caller is waiting in the queue

Feature Request Summary: 

Zendesk Talk should have the possibility to add a custom recording to be played while the caller is waiting in the queue. The recording can play after X amount of mins (or secs), and this time should be configurable per number.

Description/Use Cases: 

The possibility to play such recording would increase the customer's experience as he/she will not be waiting for a long time without any further information. This recording can also be used to remind the caller that he/she can press 1 at any time to leave a voice message (or 2 for a callback). The time to play such recording should be configurable per line so that an admin can decide to play this recording every X amount of time, e.g. play it every 1 minute while waiting.

Business impact of limitation or missing feature:

The caller has no information that actually he/she is still waiting and also may not remember that pressing 1 allows him/her to just leave a voice mail (or 2 for callback).