Considering the FV-1 runs on +3.3V, a +1.7V DC reading on the in and out pins of the FV-1 seems right - it's ~½ the supply the voltage for that chip for DC offset. Note that C3 (input side) and C8 (output side) block the DC reference from the rest of the +9V supplied sections of the circuit.
Out of curiosity, why the concern of the FV-1 in/out DC voltages?