Loudbox mini odd sound when turning on
 

Got a new Loudbox mini. When you turn it off and then on it makes a 'brrrrt' sound even with the volume on zero - anyone else have this issue?

Mine makes a little sound similar to that when I’m turning it off. It’s nothing to be concerned about. It is best to have the gains and volume at zero when turning it (or any amp) off or on.

Do you have a guitar cord plugged into the amp but not the guitar. That will oftentimes make some sound like buzzing or the cord shorting out or a bad connection. If so, plug the guitar in before judging that sound you hear. Good luck.

I went back to Guitar Center and their floor model makes the same sound, so I guess it's just a design fluke with the Mini.

It makes the sound with nothing plugged in, with gain and master on zero - a pretty comical electrical buzz (it's amplified).

I usually turn off or standby my amps when switching cables etc. to avoid the pops and buzzes, but will need to turn down the master instead with the Mini.

My loudbox mini does the same thing. While reading to see if I should be concerned, I read that the capacitors in an amp can sometimes store a charge for a short period of time, which can cause noise when turning it on. I’ve noticed, at least with mine, it doesn’t happen if it has been sitting for a while, but if I turn it off and on within a short period of time I hear the sound, so it seems like a reasonable explain to me.