I need to compile sound in application. It was working before now I installed new libs or something new and sound is gone now. here is config part. Is this mean the headers are not compatible?
...
checking sys/soundcard.h usability... yes
checking sys/soundcard.h presence... yes
checking for sys/soundcard.h... yes
checking soundcard.h usability... no
checking soundcard.h presence... no
checking for soundcard.h... no
...
here is config.log part
...
configure:10601: checking sys/soundcard.h usability
configure:10618: gcc -c -g -O2 -Wall -DFD_DATADIR='"$(pkgdatadir)"' -ffast-math -I/usr/include/SDL -D_GNU_SOURCE=1 -D_REENTRANT conftest.c >&5
configure:10624: $? = 0
configure:10638: result: yes
configure:10642: checking sys/soundcard.h presence
configure:10657: gcc -E conftest.c
configure:10663: $? = 0
configure:10677: result: yes
configure:10705: checking for sys/soundcard.h
configure:10713: result: yes
configure:10601: checking soundcard.h usability
configure:10618: gcc -c -g -O2 -Wall -DFD_DATADIR='"$(pkgdatadir)"' -ffast-math -I/usr/include/SDL -D_GNU_SOURCE=1 -D_REENTRANT conftest.c >&5
conftest.c:75:23: error: soundcard.h: No such file or directory
configure:10624: $? = 1
configure: failed program was:
| /* confdefs.h. */
...

Do you have the kernel headers installed?

cd /usr/include/SDL/
ln -s /usr/include/linux/soundcard.h

then I get this(still doesnt work)
...
checking sys/soundcard.h usability... yes
checking sys/soundcard.h presence... yes
checking for sys/soundcard.h... yes
checking soundcard.h usability... yes
checking soundcard.h presence... no
configure: WARNING: soundcard.h: accepted by the compiler, rejected by the preprocessor!
configure: WARNING: soundcard.h: proceeding with the compiler's result
checking for soundcard.h... yes
...

yeah headers are fine in fact I reinstalled headers package and still no go.

Your application is asking for "soundcard.h" in a non standard
(AFAIK) location = /usr/include .

/usr/include/linux/soundcard.h is from kernel headers.
/usr/include/sys/soundcard.h is from glibc-devel .

Suggest : Edit the application to look in the proper location.
And by the way : which application ??

Regards

No, thats impossible because I didnt change any source code of that application; it had to be something else.