Yes. For a 120v service, it's a quarter amp fuse.
A preamp is a very light load. It should not be upped to a higher value in an effort to keep it from blowing.
Very likely, the sound you heard previously means it's past time for it's normal maintenance. Electrolytic capacitors have a life of about 7-10 years. The C-1 runs fairly cool and should expect a reasonable life towards the upper end. Anything more is borrowed time and a gift. A lot of folks around here have had their units serviced due to the age. Expected and well worth it if you have an audio system you enjoy!
I was there for the 10th Carverfest! Glad you were too! Or you should have been...