Using my backpack today on a fsg clean, all good to start with. Turned it off to move it and when I turned it back on all I had was a high pitched whine. Adjusting the flow just changed the volume of the whine, so turned it off and back on and all was fine. Since then its done it half a dozen times, so opened it up to see if there was a loose connection but couldn't find one. I've also checked the fuse and that's good. It did it when it was opened up and sounds like on a low flow rate its in he controller but as I turn it up the whine seems to move towards the pump?!? Also the volt meter on the side drops to 0 when its whining. Any ideas?? Its a water genie backpack that's about 4 months old, but is used a lot any help would be great, if its FUBAR then its under warranty, and may have to crack out the trad tools again until its resolved.