rx_fm has noisy USB audio when compared with CubicSDR tuned to the same signal

[rrobinett]

Following a suggestion in another thread, I have been able to hear USB audio by disabling a signal sample scaling loop in sx_fm.
However the sound produced by rx_fm has much more background white/pink noise than the same signal listened to using CubicSDR.
As I understand it, CubicSDR includes its own Soapy API libraries but if that is true I don't know how to use those instead of the Soapy libraries I cloned on to my computer.
I am running on a basher Pi 4 with only CubicSDR and the rx_tools SW installed.