Apogee Jam...have I damaged it?

[John Cellario]

Just playing around with Garageband on a 10.9 iMac after buying an Apogee Jam.

I tried the 'line in' method via the amp and it gave much better results....however, I now have a high pitched whine coming through the Mac speakers which was not there before. It is controlled in volume by the Apogee Jam gain wheel. If I turn it right down, to eliminate the noise, there is not enough signal to record properly.

Thinking about it, I did unplug the Apogge from its USB with Garageband open.....do you think I've damaged the Apogee? It didn't make this noise before I unplugged it. It still works OK directly into the iMac.

[DaytonaRik]

I've unplugged mine plenty of times without turning off GarageBand. Are you monitoring your signal through the speakers? Possible feedback? Try using GarageBand with the Jam and headphones to see if that's the source of the problem.

[The Gedi]

Probably an earth loop betwen the amp and the Mac via the interface, seen it before, if you lift the earth on the amp or use a di box to isolate it the noise will disapear!

[John Cellario]

Thanks men....I'll experiment a bit more with the earth loop thingy and headphones. Just had a reply from Apogee to say unplugging it whilst using Garageband is not a problem.