Who said "All voice and nothing else."?

The Spartans (8th–4th century BC). Source: Plutarch, Sayings of Spartans, Anonymous 15 (233a).

What is the original Greek?

φωνὰ τὺ τίς ἐσσι καὶ οὐδὲν ἄλλο. Translated from the original Greek by Spartan Surfers.

All voice and nothing else.

The Spartans, Plutarch, Sayings of Spartans, Anonymous 15 (233a)

The source

"All voice and nothing else." The Spartans said it in Plutarch, Sayings of Spartans, Anonymous 15 (233a). Translated from the original Greek by Spartan Surfers.

"φωνὰ τὺ τίς ἐσσι καὶ οὐδὲν ἄλλο."

Original Greek, Plutarch, Sayings of Spartans, Anonymous 15 (233a). Greek: Bernardakis 1889 (Teubner) via Perseus; Said over a plucked nightingale.

Who said it

The Spartans (8th–4th century BC). Laconic sayings from Lycurgus, Leonidas, Dienekes and the mothers of Sparta, recorded by Herodotus and Plutarch.

Questions

Who said "All voice and nothing else."?: The Spartans (8th–4th century BC). Source: Plutarch, Sayings of Spartans, Anonymous 15 (233a).
What is the original Greek?: φωνὰ τὺ τίς ἐσσι καὶ οὐδὲν ἄλλο. Translated from the original Greek by Spartan Surfers.