SQ5 Mix send stuck on, even when send ch muted??

Strange thing happening. Using an SQ5. When select mix 2 then push up input fader 1 vocal to send to that mix it comes up in the monitor speaker. Then when trying to turn it down or all the way down so not sending it to that mix it is still coming out of the monitor speaker. Even if I mute Ch1 input it is still sending to Mix 2 and coming out of the wedge!
Looked through all settings and pages cannot find how to stop this. Mix1, Mix3 & Mix4 were all fine and working as they should. So it’s like its sending the signal direct to mix 2, but even when the Mic ch is muted? Very strange. I can’t find what is wrong. Any ideas or help?

Do other input do the same?

Could it be that input 1 is patched directly to output 2?

Perhaps you have it patched to a group and the group fader is up?

In your I/O section make sure that “mix ext in” is NOT selected.

Problem solved. It was the Mix ext was in. Re set it to unasigned and that’s fixed it.
Checked through and made sure all my monitor mix outputs were set the same.
Cheers everyone for the response