Can a bilateral switch block transmitter interference and can my board still produce great audio?
RF AM demodulation often occurs due to ESD input diodes or any nonlinearity due to carrier crosstalk . Poor EMC control in the design  and lack of crosstalk suppression ground plane or LPF will cause this.

These issues are usually anticipated and corrected by either RF beads on inputs to raise RF impedance and absorb Rf current with input capacitance and/or add suitable value of pF in shunt to nearest ground.  Track lengths near 1/4 wavelength on high impedance circuits are even more problematic near RF transmitters and must be corrected by the above due to wave impedance transformations.

Speaker coils are also RF resonant except they tend to force the coil radially causing a rubbing distorted sound so the same treatment as above can be tried.  The classic phone tx to tower during idle-connection test sounds like dit-dah-dah-dit repeated for a couple seconds every 5 minutes or so,  can be picked up by the speaker or a microphone or any improperly designed LF circuit at >=1GHz.

For example in some cases a 50 ohm "low mu" series SMD bead has the same effect of LPF attenuation as 10 pF shunt, but without specifics , this greatly depends on layout and circuit.