Comments Tag ?

Hi, I use Tag&Rename to tag my MP3's.
But have noticed that some files are being left with a load of digits in the comments tag, even though there is nothing in the comments field in Tag&Rename.
I only see them when I right click on the properties of the file and look at the comments field there, by the way this is the only way I can find to delete these digits.
Any ideas or any help would be very grateful
Thanks

What's the sense of deleting these digits?
And what do you see in the "PCDJ Comment" in Tag&Rename? Do you see these digits in any other ID3 tag in Tag&Rename?