DENVER -- A former owner of a digital tape recorder had no idea someone else would get hours and hours of personal conversations.

But that's what happened to "Dale," who prefers not to be identified.

When 7NEWS contacted him at his Longmont home in mid-May, Dale was shocked to hear what someone else had heard.

"I thought it was completely devoid of any files of any sort," Dale said.

Instead, a private investigator heard hours of conversations, some with Dale and Xcel.

"What is your address? Do you have your account number? Or your phone number? Yeah, my phone number," the recording said.

Dale answered several questions regarding his identity and bank account numbers.

Other chats were between him and his wife, even his daughter and her boyfriend.

"Then I heard this female's voice, with an intimate conversation," said Steve Davis, a retired police officer. "I knew that I'd probably stumbled across something I shouldn't have."

Davis was shocked by how much a criminal could have learned.

"You could've gotten where they lived, who was home alone, where Dad worked, lots of information on there where you could've committed a burglary, an assault, a robbery," Davis said. "The sky's the limit."

"It makes me feel very uncomfortable. You start scratching your head to think what all you could've discussed that would've ended up on it," Dale said.

After a few days, Dale had taken the recorder back, believing it was defective.

The digital voice telephone recorder was then purchased by Davis at a Radio Shack in Longmont. Davis paid $100 for what was billed as a brand new device.

"This is my money out of my wallet. And, so my first thought was, 'Hey, they just sold me a used tape recorder,'" Davis said.

According to protocol, Radio Shack should have cleaned the tape. But that didn't happen.

In a statement, Radio Shack took responsibility:

"RadioShack takes seriously its obligation to safeguard the privacy of our customers. In this isolated instance, our records indicate a customer returned a digital recording device and said it did not work. Unknown to us, it actually did work and apparently contained recordings of personal conversations the customer failed to erase from the memory before returning the product. The store sent the product to our repair center for evaluation, and based on their examination, the repair center determined the product did, in fact, work properly and returned it to the store for resale. Unfortunately, the repair center did not detect the original recordings and, as a result, did not clear the recordings left on it by the customer as is our standard operating procedure. We've taken this incident as an opportunity to review our systems to ensure such a thing doesn't happen again. We apologize to the original customer as well as to the customer who brought this matter it to our attention," writes Bryan Chun, Radio Shack district manager of North Colorado.

"I think what's happening is, they're repackaging these items without realizing the consumers are going to find out. And, in this case, I found out," Davis said.

As for Dale, he's a little less impressed with the digital age.

"This is all very complicated technology. It makes me just distrust myself more than anything," Dale said.