diff --git a/src/synth/fluid_synth.c b/src/synth/fluid_synth.c
index 1c83cf17..244a21b4 100644
--- a/src/synth/fluid_synth.c
+++ b/src/synth/fluid_synth.c
@@ -3632,6 +3632,13 @@ alias with buffers of \c fx. NULL buffers are permitted and will cause to skip m
 int
 fluid_synth_process(fluid_synth_t *synth, int len, int nfx, float *fx[],
                     int nout, float *out[])
+{
+    return fluid_synth_process_LOCAL(synth, len, nfx, fx, nout, out, fluid_synth_render_blocks);
+}
+
+int
+fluid_synth_process_LOCAL(fluid_synth_t *synth, int len, int nfx, float *fx[],
+                    int nout, float *out[], int (*block_render_func)(fluid_synth_t *, int))
 {
     fluid_real_t *left_in, *fx_left_in;
     fluid_real_t *right_in, *fx_right_in;
@@ -3706,7 +3713,7 @@ fluid_synth_process(fluid_synth_t *synth, int len, int nfx, float *fx[],
     while(count < len)
     {
         int blocksleft = (len - count + FLUID_BUFSIZE - 1) / FLUID_BUFSIZE;
-        int blockcount = fluid_synth_render_blocks(synth, blocksleft);
+        int blockcount = block_render_func(synth, blocksleft);
 
         num = (blockcount * FLUID_BUFSIZE > len - count) ? len - count : blockcount * FLUID_BUFSIZE;
 
diff --git a/src/synth/fluid_synth.h b/src/synth/fluid_synth.h
index 156424af..c22e61fb 100644
--- a/src/synth/fluid_synth.h
+++ b/src/synth/fluid_synth.h
@@ -212,6 +212,9 @@ void fluid_synth_process_event_queue(fluid_synth_t *synth);
 int fluid_synth_set_gen2(fluid_synth_t *synth, int chan,
                          int param, float value,
                          int absolute, int normalized);
+int
+fluid_synth_process_LOCAL(fluid_synth_t *synth, int len, int nfx, float *fx[],
+                    int nout, float *out[], int (*block_render_func)(fluid_synth_t *, int));
 /*
  * misc
  */
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 8f229c85..0b735452 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -15,6 +15,7 @@ ADD_FLUID_TEST(test_pointer_alignment)
 ADD_FLUID_TEST(test_seqbind_unregister)
 ADD_FLUID_TEST(test_synth_chorus_reverb)
 ADD_FLUID_TEST(test_snprintf)
+ADD_FLUID_TEST(test_synth_process)
 
 # if ( LIBSNDFILE_HASVORBIS )
 #     ADD_FLUID_TEST(test_sf3_sfont_loading)
diff --git a/test/test.h b/test/test.h
index 74c4bc59..2df1ebe6 100644
--- a/test/test.h
+++ b/test/test.h
@@ -4,7 +4,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 
-#define TEST_ASSERT(COND) do { if (!(COND)) { fprintf(stderr, __FILE__ ":%d assertion (%s) failed\n", __LINE__, #COND); exit(-1); } } while (0)
+#define TEST_ASSERT(COND) do { if (!(COND)) { fprintf(stderr, __FILE__ ":%d assertion (%s) failed\n", __LINE__, #COND); abort(); } } while (0)
 
 /* macro to test whether a fluidsynth function succeeded or not */
 #define TEST_SUCCESS(FLUID_FUNCT) TEST_ASSERT((FLUID_FUNCT) != FLUID_FAILED)
diff --git a/test/test_synth_process.c b/test/test_synth_process.c
new file mode 100644
index 00000000..d273bdf2
--- /dev/null
+++ b/test/test_synth_process.c
@@ -0,0 +1,86 @@
+
+#include "test.h"
+#include "fluidsynth.h"
+#include "fluidsynth_priv.h"
+#include "fluid_synth.h"
+#include <string.h>
+
+static int smpl;
+// static const int CHANNELS=16;
+static const int SAMPLES=1024;
+
+int render_one_mock(fluid_synth_t *synth, int blocks)
+{
+    fluid_real_t *left_in, *fx_left_in;
+    fluid_real_t *right_in, *fx_right_in;
+
+    int i, j;
+
+    int nfxchan = fluid_synth_count_effects_channels(synth),
+        nfxunits = fluid_synth_count_effects_groups(synth),
+        naudchan = fluid_synth_count_audio_channels(synth);
+
+    fluid_rvoice_mixer_get_bufs(synth->eventhandler->mixer, &left_in, &right_in);
+    fluid_rvoice_mixer_get_fx_bufs(synth->eventhandler->mixer, &fx_left_in, &fx_right_in);
+
+    for(i = 0; i < naudchan; i++)
+    {
+        for(j = 0; j < blocks * FLUID_BUFSIZE; j++)
+        {
+            int idx = i * FLUID_MIXER_MAX_BUFFERS_DEFAULT * FLUID_BUFSIZE + j;
+
+            right_in[idx] = left_in[idx] = (float)smpl++;
+        }
+    }
+
+    return blocks;
+}
+
+int render_and_check(fluid_synth_t* synth, int number_of_samples, int offset)
+{
+    int i;
+    float left[SAMPLES], right[SAMPLES];
+    float *dry[1 * 2];
+    dry[0] = left;
+    dry[1] = right;
+    memset(left, 0, sizeof(left));
+    memset(right, 0, sizeof(right));
+    
+    TEST_SUCCESS(fluid_synth_process_LOCAL(synth, number_of_samples, 0, NULL, 2, dry, render_one_mock));
+    
+    for(i=0; i<number_of_samples; i++)
+    {
+        TEST_ASSERT(left[i]==i+offset);
+        TEST_ASSERT(right[i]==i+offset);
+    }
+    
+    return i+offset;
+}
+
+// this test should make sure that sample rate changed are handled correctly
+int main(void)
+{
+    int off=0;
+    fluid_synth_t *synth;
+    fluid_settings_t *settings = new_fluid_settings();
+    TEST_ASSERT(settings != NULL);
+
+//     TEST_SUCCESS(fluid_settings_setint(settings, "synth.audio-channels", CHANNELS));
+//     TEST_SUCCESS(fluid_settings_setint(settings, "synth.audio-groups", CHANNELS));
+
+    synth = new_fluid_synth(settings);
+    TEST_ASSERT(synth != NULL);
+
+    off = render_and_check(synth, 100, off);
+    off = render_and_check(synth, 200, off);
+    off = render_and_check(synth, 300, off);
+    off = render_and_check(synth, 1000, off);
+    off = render_and_check(synth, 900, off);
+    off = render_and_check(synth, 800, off);
+    
+
+    delete_fluid_synth(synth);
+    delete_fluid_settings(settings);
+
+    return EXIT_SUCCESS;
+}