As to the no call list, it's in the news that companies are ignoring it or using any excuse. There are long discussions about this area but in short, use your call blockers, don't answer if the caller ID is not one you know and if it's severe get on Nomorobo.com
Is it possible to detect if an MP3 has been edited/stitched together?
I recently received a marketing/SPAM phone call from a PPI claims company. When I complained to them, telling them I was on a no call list, they said I'd given permission for them to call me, via a data collection/survey company. I remembered the call, as it was only 2 weeks prior, and was quite a strange call, due to some of the questions being asked, and I know I did not give permissions for anyone to call - (I'm very careful about survey calls). So I challenged them to provide details. They've sent an MP3 file, and you can hear the caller ask me if they can contact me, and I appear to answer yes. However, I know I didn't, so I'm 99% sure it's been edited/stitched together. Is there any way to detect stitching/editing of the MP3 file? Maybe some software which will show differences in the background noise?
It may not seem a big deal, and I've told the company not to call me again, but it's alarming & irritating, that they have gone to this level of coercion!

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