How do you filter signals of arbitrary length with complex bandpass decimator?

I am trying to impliment a 10 band octave graphic EQ and have run into some problems creating narrow enough bandpass filters for the lower octaves whilst keeping the order and computation to a minimum. I understand the Complex Bandpass Decimator can reduce computation and the order of the filters using it's multirate and multistage approach. I have managed to do this with the following code however I am not understanding how to pass a signal of artbitary length through the system, I get an error stating that the input signal must be a multiple of the decimation rate. How can I avoid this issue?

function y = bandPassLinMRMS(x, gain1, fs)

Fc = 32;
tw = 20;
bw = 20;
D = fs/(bw+(tw*2));
%fc = 64/(fs/2);
Ast = 40;
%% Bandpass 1
    bp = dsp.ComplexBandpassDecimator(D , Fc, 'SampleRate',fs,...
                                  'TransitionWidth',tw,...
                                  'StopbandAttenuation',Ast);
    freqz(bp);
    
    y = bp(x)*gain1;
end