diff --git a/tests/fate/ffmpeg.mak b/tests/fate/ffmpeg.mak
index d8f2e715901dfa9e7f55146546356f482ce3c6aa..8c25c8237f91e461335edef2dcde9db21d8c0aab 100644
--- a/tests/fate/ffmpeg.mak
+++ b/tests/fate/ffmpeg.mak
@@ -26,6 +26,10 @@ fate-mapchan: $(FATE_MAPCHAN)
 FATE_FFMPEG-$(CONFIG_COLOR_FILTER) += fate-ffmpeg-filter_complex
 fate-ffmpeg-filter_complex: CMD = framecrc -filter_complex color=d=1:r=5 -fflags +bitexact
 
+# Ticket 6603
+FATE_FFMPEG-$(call ALLYES, AEVALSRC_FILTER ASETNSAMPLES_FILTER AC3_FIXED_ENCODER) += fate-ffmpeg-filter_complex_audio
+fate-ffmpeg-filter_complex_audio: CMD = framecrc -filter_complex "aevalsrc=0:d=0.1,asetnsamples=1537" -c ac3_fixed
+
 FATE_SAMPLES_FFMPEG-$(CONFIG_COLORKEY_FILTER) += fate-ffmpeg-filter_colorkey
 fate-ffmpeg-filter_colorkey: tests/data/filtergraphs/colorkey
 fate-ffmpeg-filter_colorkey: CMD = framecrc -idct simple -fflags +bitexact -flags +bitexact  -sws_flags +accurate_rnd+bitexact -i $(TARGET_SAMPLES)/cavs/cavs.mpg -fflags +bitexact -flags +bitexact -sws_flags +accurate_rnd+bitexact -i $(TARGET_SAMPLES)/lena.pnm -an -filter_complex_script $(TARGET_PATH)/tests/data/filtergraphs/colorkey -sws_flags +accurate_rnd+bitexact -fflags +bitexact -flags +bitexact -qscale 2 -frames:v 10
diff --git a/tests/ref/fate/ffmpeg-filter_complex_audio b/tests/ref/fate/ffmpeg-filter_complex_audio
new file mode 100644
index 0000000000000000000000000000000000000000..c4246750610d0f232b41bd827f01b8832b52ec51
--- /dev/null
+++ b/tests/ref/fate/ffmpeg-filter_complex_audio
@@ -0,0 +1,10 @@
+#tb 0: 1/44100
+#media_type 0: audio
+#codec_id 0: ac3
+#sample_rate 0: 44100
+#channel_layout 0: 4
+#channel_layout_name 0: mono
+0,       -256,       -256,     1536,      416, 0x3001fb2d
+0,       1280,       1280,     1536,      418, 0xba72fc16
+0,       2816,       2816,     1536,      418, 0xba72fc16
+0,       4352,       4352,     1536,      418, 0xba72fc16