Gonna have to echo everyone else and encourage you to look at what you're playing! I use a broadly similar setup, an EHX Octave Multiplexer into a muff or rat, (Fuzzrocious ones, FWIW) and it doesn't like going below A or fast playing so note substitution and technique are key. Chording and other playing styles will help broaden the range of sounds you can get out of your bass just as much as a pedal too so it's well worth looking into.