Original Third Eye Blind Bassist Jason Slater Dead at 49

Jason's daughter, Alyssa Carlson, tells TMZ ... the rock musician died Wednesday from liver failure at a hospital in Maui. Alyssa says her dad kept his condition a secret ... telling us she just found out last month when she got a call he had landed in the hospital.

A rep for Third Eye Blind tells TMZ ... even though they had not spoken to Jason since 1996, "when a spirited member of the music scene is taken too soon it is always a sad time."

Jason was the band's bassist and backup vocalist when it formed in 1993. He recorded their first demo, and left the band after the first year. He went on to be a bassist, songwriter and producer with several other bands, including Snake River Conspiracy, Microdot, Revenge of the Triads and the rap-rock project Brougham.

Back in 2008, Jason posted this video on YouTube showing Third Eye Blind's first recording session. The band enjoyed most of its success after Jason left the band, releasing its self-titled debut album in 1997 and it's second, "Blue" in 1999.

The band's had tons of lineup changes -- singer/guitarist Stephan Jenkins and drummer Brad Hargreaves are the only original members remaining today.

Jason was 49. RIP