Shiva Purana

siva.sh/siva-purana/uma-samhita/26/25

तर्जन्या पिहितौ कर्णौ पीडयित्वा मुहूर्त्तकम्।। तस्मात्संश्रूयते शब्दस्तुदन्वह्निसमुद्भवः ।। २५ ।।

sanskrit

When the ears are closed with the index finger for a short while a kind of sound is heard as that of a blazing fire.

english translation

tarjanyA pihitau karNau pIDayitvA muhUrttakam|| tasmAtsaMzrUyate zabdastudanvahnisamudbhavaH || 25 ||

hk transliteration by Sanscript