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!
The year of the 10th Carverfest! Be there at CF2016!