Play sound in queue

hi
how can to play sound to caller in queue?

See queues.conf.sample, from the source distribution.

Note that Asterisk will try to send most audio from Queue as early media, so you may need to explicitly answer the call, if the upstream network won’t allow early media.

how can i play sound file for caller(customer) as soon as they answer a call?

Callers, by definition, do not answer calls.

sorry, i mean : how can i play sound file for caller(customer) as soon as member(agent) answer a call?
i want to play agent number for caller like call center.

core show application queue

Then look for references to “calling party”.