蛙鳴蟬噪

• 蟬噪(せんそう)蛙鳴(あめい) (sensō amei)

Yojijukugo (四字熟語), from 蛙鳴(あめい) (amei, “cries of frogs”) + 蟬噪(せんそう) (sensō, “chirps of cicadas”), noises that are just annoying and serve no purpose.

Original source is cited by Yojijukugo Jiten Online as being 平淮西碑 by Han Yu, although that appears to be false as the work does not appear to contain the term. Kanken Yojijukugo Jiten cites it to 出都來陳所乘船上有題小詩八首不知何人作有感余心者聊為和之 by Su Shi, where it appears as:

蛙鳴青草泊，蟬噪垂楊浦。
吾行亦偶然，及此新過雨。 [Classical Chinese, trad.]

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蛙鸣青草泊，蝉噪垂杨浦。
吾行亦偶然，及此新过雨。 [Classical Chinese, simp.]

Wā míng qīngcǎo bó, chán zào chuí yáng pǔ.
Wú xíng yì ǒurán, jí cǐ xīn guò yǔ. [Pinyin]

(please add an English translation of this usage example)

However, it does not appear to be used in its modern figurative meaning at this time.

(This etymology is missing or incomplete. Please add to it, or discuss it at the Etymology scriptorium. Particularly: “When did the modern figurative meaning evolve?”)

蛙(あ)鳴(めい)蟬(せん)噪(そう) • (amei sensō) 

1. (figurative) useless or frivolous speech or writing; logorrhea, prolixity, excessive noise

• 蛙鳴(あめい)雀噪(じゃくそう) (amei jakusō)
• 驢鳴(ろめい)犬吠(けんばい) (romei kenbai)

• “蛙鳴蟬噪”, in 漢検四字熟語辞典 (Kanken Yojijukugo Jiten, “Kanji Kentei Four-Character-Idiom Dictionary”) (in Japanese), second edition, Tōkyō: Japan Kanji Aptitude Testing Foundation, 2012, →ISBN, page 64