Boss GT-10B power problem

So I purchased a used Boss GT-10B from GuitarCenter. They shipped it out but it didn't come with the stock Roland PSB-1u adapter. Rather, it came with some generic adapter. Anyways, I power on the unit and after about a minute the display and all of the lights on the pedal will begin to fade away and then the pedal shuts off. I can turn it back on without a problem but then it will do the same thing over again. All of the sounds in the pedal sound perfectly fine.

Is it possible that's because I'm not using the PSB-1u adapter as required, or is it possible that there's an actual problem with the pedal?

I called my local GuitarCenter and they said that the adapter I have is under-powering the pedal. I would like to get some input before I buy the actual correct adapter.

 

any thoughts?

 

actually, I remembered I have a 1-Spot adapter (the kind that can sustain a chain of up to six pedals). This thing apparently has enough output to drive this GT-10B because the pedal is working just fine without shutting off. I hope this does the trick.

 

Do you think there's a chance that using an underpowering adapter could cause internal circuitry damage?