OK folks, I did another test with 'Mp3Test' and it picked out some mp3 files that were damaged. It also says how many percent are errors. I think it has something to do with the ID3v1 + ID3v2 Tags (I always use both of them) and I changed them in the past, so I guess that there is unused space before the mp3 starts or something...(could sombody please confirm this guess if it is right!).
So I opened that file in 'Mp3Trim' and saved it again and all of a sudden the file was not damaged anymore .
So is this a good method or is there any risk when I fix it like this?

thanks

Hey, once I've taged my mp3s with MediaJukebox and it it seems to delete my mp3 files and changed it to something like"whatever.mp3.xxxxx"

Does MP3Test work on vbr files now? I tried it a long time ago and it only worked on cbr. Also, i would try running the file thru vbr fix before "trimming" it.

The files I tested are all CBR! Are you sure that mp3Trim trims the file? I thought it only changes the size of the ID3Tag(v1) so that there is no empty space before the 'song block'. So could please somebody tell me if this procedure could have a bad side effect on a CBR file???

My prior experience with mp3Trim and downloaded mp3's from mp3 web-sites that were encoded rather shoddy and not ripped properly was a rather good one. Such as mp3's that would skip at the beginning because of a missing frame, or mp3's that would end abruptly were seemingly correctly because mp3Trim somehow repaired the damage.

I really don't know how the program fixes the errors but I am assuming it is trimming out the bad beginning or ending of an mp3, thus somewhat restoring it -- but it has no effect if there is a problem say in the middle of the file.

Thank you for your feedback, Andavari. But I would really like to hear a statement from the profs...I don't want to mess up all my mp3's, so please .

Hmm. I just ran some VBR files through MP3Trim 1.81 and it ate my APEv2 tags. It thinks the last frame is incomplete.

VBRFIX 5.3.15 also removed the APEv2 tag on default settings, and now when I check the file in EncSpot Pro 2.1 Pro it says "Gogo 3.0" instead of Lame 3.90. It also completely mangled the ID3v1 tag, filling it with random symbols and letters.

No professional here, but i'm using mp3trim for quite some time already (approx. 2 years). I've processed thousand files with it and it works fine.
One issue it had (It's definetely fixed in the newer versions) that it killed the LAME tag (Info about encoding options). It handles VBR files correctly, 90% of my mp3 files are VBR (--aps) and it worked without any problems. Unfortunately it never has been able to correct missing or invalid VBR-headers for me. Another vote for dreamliner's suggestion to use VBR-fix (Homepage) if you have problems related to VBR-header issues. But you don't have to use it before you open a VBR-file in mp3trim.

EDIT: I've never tried any mp3's with APE-tags, maybe McGee is right and it leeds to problems ... but newest version of mp3trim is 1.85beta ...
mabe it's fixed in that version!

If you only want a professional opinion you should have stated that in your original posts instead of -- in my opinion squashing someones (mine) willingness to help you.

Like someone else already replied, I too have used mp3Trim for over two years, but using it on mp3's with APE tags, or VBR mp3's I've never did that.

If you want the absolute authority on the program as in a true professional opinion I think the only way you will gain such knowledge is from the actual developer and creator of the program!

So please

mp3trim does not fix bad headers, but instead I have assumed only resamples the mp3s so that these bad headers do not show up as such anymore, but it does not fix any problems related to the bad headers and any audible problems related to these missing headers. For example, a pop created by a bad header still remains when running it through mp3trim, even if now the header is "corrected". That is why the author of the program has the option to tell you when there is something wrong with the mp3. You should only run mp3s without errors through mp3trim. What I do is use a program called mp3check to delete all ID3 info and any other errors that does not relate to the audio stream, and THEN I run these files through mp3test or encspot. If there are STILL errors, then there is something wrong with the mp3 and I delete it and find another one that does not have any errors. Of course, on file sharing systems, no one knows if bad mp3s have been run through mp3trim ALREADY, making them look to be perfectly fine, when of course there IS something wrong with them, but I usually doubt the odds that very many people have done this, so to me, if I hear nothing wrong, it is ok. You can get mp3 check here. The commandline I run removes ID3 info and fixes some other problems, make sure you have no VBR files first, there is a possibility it can mess these up, I think I have it set to ignore bitrate switching (VBRs) tho:

mp3check --recursive --cut-junk-start --cut-junk-end --ign-resync --ign-bitrate-sw --cut-tag-end "name of folder"

This is recursive, and cuts bad data off the beginning (all ID3v2 info and other errors at the beginning), cuts bad data off the end (the program will skip good ID3v1 tagging by default with cut-junk-end) and will remove all Id3v1 information (cut-tag-end). This gives me clean mp3s with most of the errors that mp3test originally picks up removed. Like I said, if mp3test STILL picks up errors, your files are either VBR files (mp3test doesn't like VBR) or they have something wrong that probably isn't fixable. I am almost certain that Encspot finds the same errors as mp3test, but Encspot will not give you an "error" message if they are VBR. Try both and see if this is correct though.

The mp3's I'm talking about don't have any errors at all...I think you are referring to the "FH's" window in the advanced mode...it doesn’t show any error there. But it still 'cleans' the mp3 a lot (in one case even 30kb's)! But still no FH's. It always says that it has a bad first / last frame or that the first / last frame is missing or invalid...this kind of stuff. So does this mean that there is reason for concern? You guys can test that with your own mp3 files...just download 'Mp3Test' and let it run through your mp3 collection...it is pretty fast though. Then open the files that are stated as 'damaged' in Mp3Trim and see what it says.

@Andavari
I'm sorry. I didn't mean it like that and I really do appreciate your feedback!!! . I just don't want to mess up my mp3 collection...since just everybody could say that it works fine...it is always hard to tell how much knowledge somebody has. But I'm still happy for every answer, also for yours . Sorry for my unlucky chosen words.

BTW. I already have contacted the author because of this. I'll keep you guy's posted.

If you put your files through Encspot, you will notice that some files are listed as complete, some will be listed as not complete, and some will be listed as maybe. This refers to incomplete, either not to standard or corrupted (possibly truncated), last frames, assuming ISO standard frame sizes, correct me if i'm wrong. As long as there are no "FH" errors as you call it or file header errors, you should be fine. I run mine through mp3trim myself to fix bad first and last headers and to "complete" the mp3s. These type of problems are usually caused by bad or non-standard ID3 tags or other corruption, and it shouldn't pose a problem at all, I am sure that it will not affect the music whatsoever. IMO to be sure that downloaded music is cleaned properly and uniformly, you should remove ALL ID3 information after using a batch ID3-to-file name renamer like TagScanner to transfer all relevant information from the tags to the file names, then clean them, and then use the program to transfer what you need back into new clean ID3 tags like you want.
From what you said about the 30 kbs, this could have been a combination of digital silence, unidentified header info, and/or possibly ID3 tag info, not sure about the last one. Hmm, mp3trim MIGHT remove ID3 tags if it needs to but I am not positive that it will do this, because isn't that a separate option (verify?) as well, I guess that could just cover ALL bases, but we are going to have to hear this directly from the author on how mp3trim by default handles ID3 info.
In conclusion, as long as you have no missing frame headers within the file, I am almost certain mp3trim will fix these mp3s perfectly. Also, let me issue a warning: Some people may know that there are illegal copies of mp3trim Pro floating around filesharing programs, but remember not to make the mistake of using this program, only the personal edition is freeware...if only the author could make the Pro version with its batch options more affordable for the single consumer, it would be very nice though, as $79.95 is a very steep price for the individual, but that is neither here nor there.

Thank you mmortal03 for your detailed report! How I said, I contacted the author and he also said as long as there are no "FH's" shown everything should be fine...I also sent him the mp3 file from which the cleaning cycle removed 30kb and he said that it was only some sort of information from the used encoder program...but this information was totally useless.

I'm using only the freeware program of 'Mp3Trim', since I only use it for purposes like removing last bad frames etc. I don't need the Pro Version...and I do agree that it is hella expansive!