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Daltrey -- who experienced a cancer scare earlier this year that resulted in an operation to remove a pre-cancerous growth on one of his vocal chords -- told Rolling Stone, "I was having terrible trouble hearing what I was singing and it did get to me.
"In fact, I've been suffering for quite a few of the previous tours. I never understood that if you sweat as much as I used to every night, you drain your body of salts."
It's not just his own health the frontman is concerned about. "Pete [Townshend] is having terrible hearing problems at the moment," he said.
Daltrey added, "There's nobody I'd rather be on stage with than Pete. But equally, I don't want to be on stage with him destroying the last bit of his hearing. That would be completely foolish. He's a composer."
As for the future of the band -- despite health issues -- the singer isn't ready to entertain thoughts of retirement. "We're in the last bits of our career," he said. "I feel that we owe it to the public that supported us all these years to go down with us. I had a real scare with my voice a couple of years ago, but now I'm singing better than ever. And it made me just want to use it till the day I can't."