When I connect the Mackie 1642-vlz3 from the "direct outs" to the line level inputs of the D3200 there is noise/hum (except for channel 1). There is no noise/hum in the XLR inputs. I have two Mackies. They are the same. So if I switch between them there shouldn't be different and they aren't so I still hear the noise/hum. But if plug something other than the Mackies, there is no noise/hum. I have plugged an Alesis mixer in there was no noise/hum. I plugged a mic directly into the line inputs and no noise/hum. You may say that I should get rid of the Mackies. Well they are new and I am not yet convinced that they are the problem. Could it be there is something in the effects/eq section that may be open and I'm just not seeing it or not looking in the right places? Do you have any idea as to what would make it do this?

This is not a powered mixer and so you must connect a power amp to the "line level" outputs of the mixer. Other "no output" problems could be related to buss assignments and other signal routing issues. Check for output by connecting "Main Out" left or right to a guitar amp input instead BUT turn all volumes down to zero before conductiong this test as guitar amps are designed for "Microphone" level inputs. Owners and Hookup manuals can be found here...

http://www.mackie.com/products/1604vlz3/

I would be surprised with all 16 mics active that you can't reach near a clipping level... Of course if you only have 8 mics active we would not expect to reach unity levels. Make sure this board is powered from the same receptacle as your amps. Powering it from building power at opposite ends of a room from where the amps are powered is asking for damage from ground bounce. The pros run a power back to the mixer alongside the snake.
Your trims will be fairly wide open for dynamic mics and your faders should be around unity during use. It is nice if the main fader can be around 50% or more. Use BALANCED lines everywhere including those running to the amps.

The problem is that card has only UNBALANCED inputs. You really need balanced or first run the mixer outputs through a DI backwards. Frankly, I would recommend NOT using a card within the PC as there is so much digital noise. Use either a USB or Firewire external convertor and for goodness sakes use balanced lines from teh Mackie... ALL interconnected equipment needs to be powered from the same receptacle or source. M Audio, Roland/Cakewalk and Presonus all make cards as do others.

This is probably a loose or damaged cable within. These channels I believe are grouped in groups of eight, so two groups would be dead for this function.

Here is your schematic:

http://elektrotanya.com/mackie_1642-vlz-pro_full-sm.rar/download.html

The manual can be downloaded from the link below.

Dan

Link: http://www.mackie.com/pdf/archive/cr1604_om.pdf

If the hum is observable in headphones, then it is likely a power supply problem, usually a dried out electrolytic filter capacitor.

There are LED's all over these and you don't say which are lit... If they are mute or solo LED check the switches for a solo button or mute that is set.

IF they are the output level LED's plug in a set of phones and crank the phone volume up to losten if there is feedback or oscillation that is causing this.

HUM PICKUP due to a ground loop could be causing this. Make sure that ANYTHING connected to the unit that is also powered receives pwer from the SAME receptacle. If you have devices that receive power from a different receptacle you MAY have a ground loop. Noise on power lines can DAMAGE the equipment due to excedding the common mode input and output capability of the unit.

Finally, a strong local radio transmitter MAY be interfering. Sometimes the interference can go backward into the output lines to trigger the indicators.

As a test, when event occurs again, start unplugging anything connected to the mixer and see if disconnecting anything stops the problem. If you can have the problem with ONLY the power connected, then check if you have inadvertently created a loop within the unit by your settings.

Please refer to the "signal flow" diagrams in your user manual to see the possible feedback paths you can cause a loop to form.

REMEMBER the oscillation MAY be occuring well above the frequency you can hear !!!!

If you have access to an oscilloscope that would see if there is an oscillation going on.

Hi kielhunt
It sounds like power supply issues.
You may have bad capacitors and/or bad regulators.
If you have a multimeter you can get in there and check the dc voltages for ripple(ac voltage mixed with dc) or over/under voltages along the +/- 15volts lines.
Good luck

Make sure the mic/line button is selected when trying to input from teh external inputs.

Don't know your setup but have you checked out any possible Hum loops? Have you updated any firmware updates? Is your mains input clean (no spikes or very short drop outs of voltage)? Are you near any possible RFI, e.g. Taxi's or CBr's? The list goes on so check out the Mackie forum on the web for more. Good Luck...
Regards,
Frank.