diff --git a/libaf/af.c b/libaf/af.c
index d9f234aa48..bae66ce8b0 100644
--- a/libaf/af.c
+++ b/libaf/af.c
@@ -72,7 +72,7 @@ int* af_cpu_speed = NULL;
 
 /* Find a filter in the static list of filters using it's name. This
    function is used internally */
-af_info_t* af_find(char*name)
+static af_info_t* af_find(char*name)
 {
   int i=0;
   while(filter_list[i]){
@@ -100,7 +100,7 @@ af_instance_t* af_get(af_stream_t* s, char* name)
 
 /*/ Function for creating a new filter of type name. The name may
   contain the commandline parameters for the filter */
-af_instance_t* af_create(af_stream_t* s, char* name)
+static af_instance_t* af_create(af_stream_t* s, char* name)
 {
   char* cmdline = name;
 
@@ -152,7 +152,7 @@ err_out:
 /* Create and insert a new filter of type name before the filter in the
    argument. This function can be called during runtime, the return
    value is the new filter */
-af_instance_t* af_prepend(af_stream_t* s, af_instance_t* af, char* name)
+static af_instance_t* af_prepend(af_stream_t* s, af_instance_t* af, char* name)
 {
   // Create the new filter and make sure it is OK
   af_instance_t* new=af_create(s,name);
@@ -176,7 +176,7 @@ af_instance_t* af_prepend(af_stream_t* s, af_instance_t* af, char* name)
 /* Create and insert a new filter of type name after the filter in the
    argument. This function can be called during runtime, the return
    value is the new filter */
-af_instance_t* af_append(af_stream_t* s, af_instance_t* af, char* name)
+static af_instance_t* af_append(af_stream_t* s, af_instance_t* af, char* name)
 {
   // Create the new filter and make sure it is OK
   af_instance_t* new=af_create(s,name);
@@ -226,7 +226,7 @@ void af_remove(af_stream_t* s, af_instance_t* af)
 /* Reinitializes all filters downstream from the filter given in the
    argument the return value is AF_OK if success and AF_ERROR if
    failure */
-int af_reinit(af_stream_t* s, af_instance_t* af)
+static int af_reinit(af_stream_t* s, af_instance_t* af)
 {
   do{
     af_data_t in; // Format of the input to current filter
diff --git a/libaf/af_hrtf.c b/libaf/af_hrtf.c
index f8d14b318e..ff4e53aba8 100644
--- a/libaf/af_hrtf.c
+++ b/libaf/af_hrtf.c
@@ -74,7 +74,7 @@ static float conv(const int nx, const int nk, float *sx, float *sk,
 }
 
 /* Detect when the impulse response starts (significantly) */
-int pulse_detect(float *sx)
+static int pulse_detect(float *sx)
 {
     /* nmax must be the reference impulse response length (128) minus
        s->hrflen */
@@ -90,7 +90,7 @@ int pulse_detect(float *sx)
 
 /* Fuzzy matrix coefficient transfer function to "lock" the matrix on
    a effectively passive mode if the gain is approximately 1 */
-inline float passive_lock(float x)
+static inline float passive_lock(float x)
 {
    const float x1 = x - 1;
    const float ax1s = fabs(x - 1) * (1.0 / MATAGCLOCK);
@@ -100,7 +100,7 @@ inline float passive_lock(float x)
 
 /* Unified active matrix decoder for 2 channel matrix encoded surround
    sources */
-inline void matrix_decode(short *in, const int k, const int il,
+static inline void matrix_decode(short *in, const int k, const int il,
 			  const int ir, const int decode_rear,
 			  const int dlbuflen,
 			  float l_fwr, float r_fwr,
@@ -207,7 +207,7 @@ inline void matrix_decode(short *in, const int k, const int il,
 #endif
 }
 
-inline void update_ch(af_hrtf_t *s, short *in, const int k)
+static inline void update_ch(af_hrtf_t *s, short *in, const int k)
 {
     const int fwr_pos = (k + FWRDURATION) % s->dlbuflen;
     /* Update the full wave rectified total amplitude */
diff --git a/libaf/filter.c b/libaf/filter.c
index 4352a34d7c..a637bb6df3 100644
--- a/libaf/filter.c
+++ b/libaf/filter.c
@@ -274,7 +274,7 @@ int af_filter_design_pfir(unsigned int n, unsigned int k, _ftype_t* w, _ftype_t*
    Note that a0 is assumed to be 1, so there is no wrapping
    of it.  
 */
-void af_filter_prewarp(_ftype_t* a, _ftype_t fc, _ftype_t fs)
+static void af_filter_prewarp(_ftype_t* a, _ftype_t fc, _ftype_t fs)
 {
   _ftype_t wp;
   wp = 2.0 * fs * tan(M_PI * fc / fs);
@@ -310,7 +310,7 @@ void af_filter_prewarp(_ftype_t* a, _ftype_t fc, _ftype_t fs)
    Return: On return, set coef z-domain coefficients and k to the gain
    required to maintain overall gain = 1.0;
 */
-void af_filter_bilinear(_ftype_t* a, _ftype_t* b, _ftype_t* k, _ftype_t fs, _ftype_t *coef)
+static void af_filter_bilinear(_ftype_t* a, _ftype_t* b, _ftype_t* k, _ftype_t fs, _ftype_t *coef)
 {
   _ftype_t ad, bd;