A Rule of Thumb says the higher the density of a propagating medium the higher the velocity of propagation of sound (or other disturbance) through it. If a medium composed of interetheric substance has a near infinite density sound would propagate through it nearly instantly. As it is a given there are MANY Etheric (quantum) and interetheric (subquantum) substances much finer than light or a media composed of photons then we can see the velocity of light is nowhere near any limit on vibratory wave propagation rates or velocities.
Sound waves are conventionally understood as air molecules bouncing into each other. Anyone who has ever played pool or billiards knows this cannot be true. SVP has another view as illustrated in Keely's laws listed below. The entire process of sound propagation is not confined to these two laws.
Law of Oscillating Atoms
"All atoms when in a state of tension are capable of oscillating at a pitch inversely as the cube of their atomic weights, and directly as their tension from 42 to 63 octaves per second, producing the creative force (Thermism), whose transmissive force (Rad-energy) propagated in solid, liquid, and gaseous ether, produces the static effects (Cohesion and Chemism) on other atoms of association, or dissociation, according to the Law of Harmonic Attraction and Law of Repulsion.
Scholium: Dark radiant heat begins at absolute zero temperature, and extends through light, chemical rays, actienic rays, and infra-violet rays, up to the dissociation of all molecules to the 63rd octave." (Keely, pre 1894) Dashed Against the Rock
Law of Vibrating Atomolic Substances
"Atoms are capable of vibrating within themselves at a pitch inversely as the Dyne (the local coefficient of Gravity), and as the atomic volume, directly as the atomic weight, producing the creative force (Electricity), whose transmissive force is propagated through atomolic solids, liquids, and gases, producing induction and the static effect of magnetism upon other atoms of attraction or repulsion, according to the Law of Harmonic Attraction and Repulsion.
Scholium: The phenomenon of Dynamic Electricity through a metallic conductor and of induction are identical. In a metallic conductor, the transmission is from atom to atom, through homologous interstices, filled with ether, presenting small areas in close proximity. In crystalline structures, heat, which expands the atoms, by twisting them produces striae, increases the resistance, etc. Between parallel wires and through air the induction takes place from large areas through a rarefied medium composed of a mixture of substances, whose atoms are separated by waves of repulsion of various pitches, discordant to electric vibrations; the said atoms sympathetically absorb the vibrations and dissipate from themselves, as centers, concentric waves of electric energy which produces heat and gravism." Keely
6.8 - Proportionate and Relative Geometries
9.12 - Velocity of Sound and its Propagation Rate are Proportional
12.00 - Reciprocating Proportionality
3.13 - Reciprocals and Proportions of Motions and Substance
13.15 - Principle of Proportion
Figure 6.17 - Areas and Volumes - Relations and Proportions
Figure 6.19 - Sphere to Cube - Relations and Proportions
Figure 14.10 - Proportionate Tonal Relations dictate Contraction or Expansion
Law of Assimilation
Part 12 - Russells Locked Potentials
Table 2 - Controlling Modes and Proportions