Travis Barker Drums to Baby's Heartbeat in Delivery Room, Gets Roasted Online

Travis Barker played the drums to his baby's heartbeat while in the delivery room with Kourtney Kardashian before the kiddo was born ... and folks online are calling it a bit "ick."

The Blink-182 drummer did what he does best in the clip, shared by the man himself on Thursday ... with the caption, "Practicing to my babies [sic] heartbeat."

While some couldn't help but point out he's one of the best drummers in the game, others chimed in with their distaste for the delivery room performance -- with one saying Kourtney, who seems to be recording the vid, has to have "angel-like" patience.

Trav's TikTok prompted comments like, "I would literally be so annoyed I couldn't do it," "That would've driven me up the wall" and, "Imagine being in the room next to this."

It wasn't all bashing, though ... plenty of folks simply congratulated Travis and Kourtney on their new baby, calling the music "so beautiful."

As we reported, Kourtney and Travis left Cedars-Sinai on Tuesday after spending multiple days at the hospital ... although it's still unclear exactly what day their baby, Rocky, was actually born.