Roland Cube Street amp won't power on? Anyone know where to buy a fuse if it is blown or how to check if it is just a fuse? What else should I check and how? Thank You.

Hey guys, so I know that this thread is rather ancient now, but I just surfed here because I had a similar problem with mine, I managed to fix the problem of the power not turning on with either the power or battery, after it working and then just randomly not turning on.
Here's what I did:
I opened the speaker grill, and took out the right speaker, everything looked fine inside on the circuit board, thinking it might be a fuse - I started looking for it- to no avail.
I was just about to give up when I accidentally bumped the wires to the power switch, and the light came on! Huzzah!!
I played with the wires a bit because the light kept flickering and would turn on once then not again.
I pulled the wires off the switch and took the switch out of the box, then used my pocket knife to scratch away some discoloration from the terminals on the switch, then re-attached the wires, but only put them on halfway, and the problem was solved!
This was only a quick fix, and I went out the next day to Altronics (I'm in Australia) to buy a replacement power switch.
I re-attached the power wires to the new switch, slid them on the whole way and I haven't had a problem with it since!
I hope this helps someone before they take it to a technician who will probably do exactly what I did and charge you $300
Happy Jamming legends! Rock on!

I would take it to a technician.