Pre hiss in 1ch 816x.

Any thoughts about it?? Have tried even factory reset. Other channels working fine but quite audible hiss on 1 ch. Bad pre??

With instrument (high impedance) selected, I get quite a bit of hiss with the preamp gain turned up. Virtually noise free when the input is set to normal impedance.

Does it looks like this (see attachement). I put the gain on input 2 completely up (there is nothing connected to input 2).
When the gain is turned down the lights don’t come up.

By the way I don’t know what’s going on with the other inputs I have cables connected to them but
the equipment I connected is off. When I put the gain up I get noise till 35 db.
MR816x.png

I just recently picked up an MR816scx and ran into the same problem. It has a very loud audible hum when using the input for direct guitar/bass recording, which is louder than the input signal. I have a temporary fix by using the pad and a VST noise gate, but I can still hear that hum. It sounds like I am using a ground lifted cable. I tried different TS cables with the same results. I also tried all of my guitars and got the same results. I get this hum with both the hi-z and standard line in toggle switch. Any guidance on this would be great!

Thanks!

Cole

Enclosed is a screenshot of another 816 (csx in this case) and in normal operation with the gain down there is nothing to see in Stereo in 3 but with the gain completely open you can see again some hum. By the way there is no cable connected to Stereo in 3. In all the other channel inputs are cables connected but the gain is completely turned to the left.

So I don’t know if you can make a conclusion from this that alle the MR816 have the same problem or mabye this is normal not only with the MR816 but also with other soundcards.
More results are welcome also from other soundcards because I am qurious what happens to them when you turn the gain completely up.
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