It is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) heard a sound that terrified him, then Jibril (peace be upon him) came to him, and the Messenger of Allah (peace and blessings be upon him) asked: "O Jibril! What is this sound?" He said: "This is a rock that has been falling from the edge of Hell for seventy years, and this is the moment it has reached its bottom, so Allah Almighty wished to let you hear its sound."
After that day, the Messenger of Allah (peace and blessings be upon him) was never seen laughing fully (with his whole mouth) until he passed away.
Hadith Referenceالمعجم الأوسط / باب الألف / 815
Hadith Gradingمحدثین:إسناده ضعيف لضعف إسماعيل بن قيس الأنصاري
Hadith Takhrij«قال الهيثمي: فيه إسماعيل بن قيس الأنصاري وهو ضعيف «مجمع الزوائد ومنبع الفوائد، ج 10، ص 389»»