Fuse holder #7 sparks

[abscate]

It's is probably off scale to read the low amps. Most radios do pull some current to keep the stations in memory, so that's not a problem.

Try measuring the current at the fuse holder where you see the spark. Can you use a 1.0 amp setting on your VOM?

[mikealder]

Did you use the correct terminal on the meter for the ten amp range, the neg is common to all settings but the red lead has its own connection terminal on the meter when using the 10A range on most meters. If you connect the leads to the same points on the meter you use when reading Voltage with it set to 10A range the meter will read zero - Mike

[Volvo Manic]

Has anyone else solved this problem? I thought it might be the radio head, so I pulled and disconnected the radio connections.
Power still off, plug in another fuse and it is zapped very loudly before it even gets close to getting seated.
I still have the amp and disused 6 CD changer hooked up. How do I disconnect the AMP and are there any other live wires coming off of fuse 7?
It is a Volvo 1995 850 Turbo

My white and brown wires on the radio harness all go to ground, as does the brown/green wire and one other wire that has two XX stamped in white on it. The black negative wires also go to ground as expected.