Mag 9.5 making gurgling sound

[PineHill]

I woke up this morning and my Mag 9.5 for my UGJ was making a loud annoying gurlging sound as if there was air in it or something wrong with the impeller.
Help please?
Chris

[elk]

could have substrate sucked in

[PineHill]

I took a look inside the Mag9.5 today and nothing seemed wrong.  So I put it back in and the noise was still present.
Any other ideas are to what is wrong?
Also what are some good reliable but most importantly QUITE pumps that push ~800gph?
Thanks

[PineHill]

Tried shaking all the air out of the pump while it was under water and some came out.  However the sound is still there.
Any thoughts or advice?

[KLKelly]

I've had mine make sounds before right before it died.  Mines only a Mag5 though.  It was the wierdest thing when it did die if I lifted it out of the water and dunked it again it started working again with that sound still there.  Eventually it stopped restarting.  I had to replace the impeller.  I'm don't know enough about pumps and tank hardware to say that this is the same thing.  I have to start and stop my magpump often as I use it in my aeration setup not for a sump.  I don't think they are meant to be turned on and off often.