ltspice simulations is so slow
As @Huisman hinted at:

Your sampling rate is 44.1 kHz, yet you're simulating this circuit with a simulation rate of 1/10ns = 100 MHz. That means for every time the input changes, 100 MHz / (44.1 kHz), i.e. more than 2000 simulation steps, are performed.

That is very likely far more than necessary. Try with maybe 1000 ns of step size and see whether that changes the result in any way. If it does: your system needs better low-pass characteristics – it really shouldn't change anything, considering your recordings can't even represent anything above 22.05 kHz.