Missing some sounds on AUX output of mixer

[mullin]

We have several inputs connecting to the mixer directly.
- Guitar
- Keyboard
- Flute (By condensor mic)
- Vocal (Normal mic)

But, if we use the AUX output, only the Vocal sound will be lost. But, if we use the MONO output, it's fine.

Any ideas on this? Btw, sorry that I forgot the model I just used.

 

[Whale Bone]

Of great help would be details of the mixer and how you've set up the channels you're using.

In the absence of that, however:
The Mono out is probably a mono version of the Mains out (I'm guessing), so that would be independent of the aux buss.

Have you tried:
- checking the AUX send level on the channel the mic is in
- checking that you are using the same aux as on the other channels. If the AUX send you are using is switchable, e.g. 3 & 4 can be switched to be 5 & 6, is it switched correctly?
- using a different channel for the vocals - maybe the AUX send on that channel is bad
- Is there a pre/post switch for the AUX you are using? Exercise the switch to possibly clean the contacts.
- is there a jumper (inside) to set pre or post? Is it missing or ar the pins dirty?