Here is the manual if you don't have one:http://www.mackie.com/pdf/archive/cr1604_om.pdf. There are solo buttons for each channel. There is also an auxiliary return solo button. There is also a solo to main button. These buttons are all inter related. Is your main output mute button in or out? Read the manual carefully as there are a myriad of combinations you can use. Have a look at the trouble shooting guide on page 21. If you can't find a solution try contacting Mackie. Let me know if this helps.
Answers & Comments
Here is the manual if you don't have one:http://www.mackie.com/pdf/archive/cr1604_om.pdf. There are solo buttons for each channel. There is also an auxiliary return solo button. There is also a solo to main button. These buttons are all inter related. Is your main output mute button in or out? Read the manual carefully as there are a myriad of combinations you can use. Have a look at the trouble shooting guide on page 21. If you can't find a solution try contacting Mackie. Let me know if this helps.