Good for you...have you picked out a new preamp yet? It's a simple up grade if you are handy with a soldering iron and can read a simple schematic. You can get the Bartolini US NTMB module for about $99 and the pots you need for another $20.
I've read a number of posts regarding this bass.
The common thread is that the MK1 Bart pups are great but maybe not the MK1 pre amp
It's the same pre on my 44-02 which I like OK (but still not sure it's a keeper)
Which pre do you recommend and what didn't you like about it on the 44-01