# Unique background music for the queue
The function can be useful if there is a need to play an advertising audio file instead of background music. You can assign your own file to each queue.
1. Go to the section "**Telephony**" -> "**Sound files**" -> "**Music on hold**"
Music on hold section
2. Add media files:
New audio file
3. After saving the media file, copy its ID from the browser address bar. For example , in a link like "" the identifier is the number **5**.
ID of the media file
4. Go to the "**System**" -> "**System file customization**"
"System file customization" section
5. Open the file "**/etc/asterisk/extensions.conf**" for editing
"extensions.conf" file
6. Paste the following code at the end of the file:
```php
[queue-pre-dial-custom]
exten => 2001,1,Set(CHANNEL(musicclass)=moh-5)
exten => 2002,1,Set(CHANNEL(musicclass)=moh-6)
exten => _X!,2,return
```
Code for extensions.conf
{% hint style="success" %}
According to this example, for the queue with the number "**2001**", a file with the ID **5** will be played in the background, for the queue "**2002**", a file with the ID **6**
{% endhint %}
