The former Eurythmics star was stunned when Sony BMG stopped answering her phone calls just weeks before her contract was due to expire.
Lennox, 53, insists she was shocked at the way she was treated by the company which once hailed her as "one of the finest musical voices of the age".
She says, "They totally ignored me. It was bizarre. It was a kick in the teeth. They didn't return my phone calls or emails for three weeks. I'm trying to find out what's behind it.
"Probably a good thing I'm no longer with them - mild understatement. Unless it's them trying to tell me something... Hello!"
The singer admits she has been left contemplating her future in the music industry.
She adds, "It feels like I'm spent, as if I've completely run out of energy. I'm going to take my time over the coming months to figure out what to do with this freedom."
Lennox's last album, Songs of Mass Destruction, charted at number nine in the Billboard 200 chart in October 2007, selling a healthy 78,000 copies during its first week of release in the U.S.
Source: WENN