Before even attempting to report a bug in libsndfile please make sure you have read the Frequently Asked Questions. If you are having a problem writing code using libsndfile make sure you read the Application Programming Interface documentation.
That said, I am interested in finding and fixing all genuine bugs in libsndfile. Bugs I want to fix include any of the following problems (and probably others) :
When submitting a bug report you must include :
If libsndfile compiles and installs correctly but has difficulty reading a particular file or type of file you should run the sndfile-info program (from the examples directory of the libsndfile distribution) on the file. See here for an example of the use of the sndfile-info program.
Please do not send me a sound file which fails to open under libsndfile unless I specifically ask you to. The above information should usually suffice for most problems.
Once you have the above information you should submit a ticket on the libsnfile github issue tracker.