You have huge 10uF input capacitors feeding opamps with an input impedance of only 1k ohms and a voltage gain of 100. For low impedance microphones?
The input opamps will be overloaded with line-level signals.
The input capacitors should be 220nF poly type and the opamp's input resistor should be 100k for a voltage gain of 1.
If you remove U1A3 and U1B3 then the output level of the circuit depends on the resistance of the load.
Remove C5, R183, C12, U1A, r1 and R11 and the same parts on the other channel.
U1A3 and U1B3 can drive the filters and the CD4066 directly.
The CD4066 is not biased and not powered correctly.
With inputs from -8V to +8V then it should have a dual-polarity supply of -8v and +8V.
Your simulation shows an opamp with a gain of about 200,000 because it doesn't have the series input resistor that normally feeds an inverting opamp.
The 220nF input capacitor blocks frequencies below about 300Hz (or less) and the very high gain cuts high frequencies.
+90dB is a voltage gain of 32,000.
A resistor to ground at the input of an inverting opamp does not do anything because the feddback resistor makes the input at the same voltage as the non-inverting input which is ground in your circuit.