diff --git a/tests/fate/filter-audio.mak b/tests/fate/filter-audio.mak
index 6125a37..473b8ae 100644
--- a/tests/fate/filter-audio.mak
+++ b/tests/fate/filter-audio.mak
@@ -156,7 +156,27 @@ fate-filter-pan-stereo3: CMD = framecrc -ss 3.14 -i $(SRC) -frames:a 20 -filter:
 FATE_AFILTER-$(call FILTERDEMDECENCMUX, PAN, WAV, PCM_S16LE, PCM_S16LE, WAV) += fate-filter-pan-stereo4
 fate-filter-pan-stereo4: tests/data/asynth-44100-2.wav
 fate-filter-pan-stereo4: SRC = $(TARGET_PATH)/tests/data/asynth-44100-2.wav
-fate-filter-pan-stereo4: CMD = framecrc -ss 3.14 -guess_layout_max 0 -i $(SRC) -frames:a 20 -filter:a "pan=4C|c0=c0-0.5*c1|c1=c1+0.5*c0|c2=0*c0|c3=0*c0"
+fate-filter-pan-stereo4: CMD = framecrc -ss 3.14 -guess_layout_max 0 -i $(SRC) -frames:a 20 -filter:a "pan=2C|c0=c0-0.5*c1|c1=c1+0.5*c0"
+
+FATE_AFILTER-$(call FILTERDEMDECENCMUX, PAN, WAV, PCM_S16LE, PCM_S16LE, WAV) += fate-filter-pan-upmix1
+fate-filter-pan-upmix1: tests/data/asynth-44100-2.wav
+fate-filter-pan-upmix1: SRC = $(TARGET_PATH)/tests/data/asynth-44100-2.wav
+fate-filter-pan-upmix1: CMD = framecrc -ss 3.14 -guess_layout_max 0 -i $(SRC) -frames:a 20 -filter:a "pan=4C|c0=c0-0.5*c1|c1=c1+0.5*c0|c2=0*c0|c3=0*c0"
+
+FATE_AFILTER-$(call FILTERDEMDECENCMUX, PAN, WAV, PCM_S16LE, PCM_S16LE, WAV) += fate-filter-pan-upmix2
+fate-filter-pan-upmix2: tests/data/asynth-44100-4.wav
+fate-filter-pan-upmix2: SRC = $(TARGET_PATH)/tests/data/asynth-44100-4.wav
+fate-filter-pan-upmix2: CMD = framecrc -ss 3.14 -i $(SRC) -frames:a 20 -filter:a "pan=9C|c0=c0-c1|c1=c2+c3|c2=c0+c1|c3=c2-c3|c4=c1-c0|c5=c3+c2|c6=c1+c0|c7=c3-c2|c8=c0-c3"
+
+FATE_AFILTER-$(call FILTERDEMDECENCMUX, PAN, WAV, PCM_S16LE, PCM_S16LE, WAV) += fate-filter-pan-downmix1
+fate-filter-pan-downmix1: tests/data/asynth-44100-4.wav
+fate-filter-pan-downmix1: SRC = $(TARGET_PATH)/tests/data/asynth-44100-4.wav
+fate-filter-pan-downmix1: CMD = framecrc -ss 3.14 -i $(SRC) -frames:a 20 -filter:a "pan=2c|FL<FL+0.5*FC+0.6*BL+0.6*SL|FR<FR+0.5*FC+0.6*BR+0.6*SR"
+
+FATE_AFILTER-$(call FILTERDEMDECENCMUX, PAN, WAV, PCM_S16LE, PCM_S16LE, WAV) += fate-filter-pan-downmix2
+fate-filter-pan-downmix2: tests/data/asynth-44100-11.wav
+fate-filter-pan-downmix2: SRC = $(TARGET_PATH)/tests/data/asynth-44100-11.wav
+fate-filter-pan-downmix2: CMD = framecrc -ss 3.14 -i $(SRC) -frames:a 20 -filter:a "pan=5C|c0=0.7*c0+0.7*c10|c1=c9|c2=c8|c3=c7|c4=c6"
 
 FATE_AFILTER_SAMPLES-$(call FILTERDEMDECENCMUX, SILENCEREMOVE, WAV, PCM_S16LE, PCM_S16LE, WAV) += fate-filter-silenceremove
 fate-filter-silenceremove: SRC = $(TARGET_SAMPLES)/audio-reference/divertimenti_2ch_96kHz_s24.wav
diff --git a/tests/ref/fate/filter-pan-downmix1 b/tests/ref/fate/filter-pan-downmix1
new file mode 100644
index 0000000..47d5044
--- /dev/null
+++ b/tests/ref/fate/filter-pan-downmix1
@@ -0,0 +1,26 @@
+#tb 0: 1/44100
+#media_type 0: audio
+#codec_id 0: pcm_s16le
+#sample_rate 0: 44100
+#channel_layout 0: 3
+#channel_layout_name 0: stereo
+0,          0,          0,      512,     2048, 0xccb10170
+0,        512,        512,      512,     2048, 0xc51cf8e7
+0,       1024,       1024,      512,     2048, 0x959eef2d
+0,       1536,       1536,      512,     2048, 0x559f0751
+0,       2048,       2048,      512,     2048, 0x4c4c08e1
+0,       2560,       2560,      512,     2048, 0x41c3fd6f
+0,       3072,       3072,      512,     2048, 0x4c92f8d2
+0,       3584,       3584,      512,     2048, 0x9defee05
+0,       4096,       4096,      512,     2048, 0x2d33f4dc
+0,       4608,       4608,      512,     2048, 0xd854eeca
+0,       5120,       5120,      512,     2048, 0xdb55eaf7
+0,       5632,       5632,      512,     2048, 0x2bac060d
+0,       6144,       6144,      512,     2048, 0x91beec0f
+0,       6656,       6656,      512,     2048, 0x3262f0da
+0,       7168,       7168,      512,     2048, 0xf00708a6
+0,       7680,       7680,      512,     2048, 0xc90cfa02
+0,       8192,       8192,      512,     2048, 0x09e9f413
+0,       8704,       8704,      512,     2048, 0xcd0d0c36
+0,       9216,       9216,      512,     2048, 0x6f6bff82
+0,       9728,       9728,      512,     2048, 0x18a40912
diff --git a/tests/ref/fate/filter-pan-downmix2 b/tests/ref/fate/filter-pan-downmix2
new file mode 100644
index 0000000..8d3ee10
--- /dev/null
+++ b/tests/ref/fate/filter-pan-downmix2
@@ -0,0 +1,26 @@
+#tb 0: 1/44100
+#media_type 0: audio
+#codec_id 0: pcm_s16le
+#sample_rate 0: 44100
+#channel_layout 0: 0
+#channel_layout_name 0: 5 channels
+0,          0,          0,      186,     1860, 0x2480a20e
+0,        186,        186,      186,     1860, 0xde9e9c40
+0,        372,        372,      186,     1860, 0xc497b2a0
+0,        558,        558,      186,     1860, 0xe5a8a2d7
+0,        744,        744,      186,     1860, 0x01c09b6a
+0,        930,        930,      186,     1860, 0xb26fae2f
+0,       1116,       1116,      186,     1860, 0x1292a9ab
+0,       1302,       1302,      186,     1860, 0xe7a79136
+0,       1488,       1488,      186,     1860, 0x57dc81a3
+0,       1674,       1674,      186,     1860, 0xc13b9a1b
+0,       1860,       1860,      186,     1860, 0xdf7c9fd6
+0,       2046,       2046,      186,     1860, 0x4d769cff
+0,       2232,       2232,      186,     1860, 0xb8b79977
+0,       2418,       2418,      186,     1860, 0xd287989f
+0,       2604,       2604,      186,     1860, 0xc2a38f03
+0,       2790,       2790,      186,     1860, 0xd7149438
+0,       2976,       2976,      186,     1860, 0xc3719081
+0,       3162,       3162,      186,     1860, 0xb9fba1a3
+0,       3348,       3348,      186,     1860, 0xe92cb2de
+0,       3534,       3534,      186,     1860, 0x9dd9b272
diff --git a/tests/ref/fate/filter-pan-stereo4 b/tests/ref/fate/filter-pan-stereo4
index 87c70a7..6d10ed6 100644
--- a/tests/ref/fate/filter-pan-stereo4
+++ b/tests/ref/fate/filter-pan-stereo4
@@ -3,24 +3,24 @@
 #codec_id 0: pcm_s16le
 #sample_rate 0: 44100
 #channel_layout 0: 0
-#channel_layout_name 0: 4 channels
-0,          0,          0,     1024,     8192, 0xdaadfc44
-0,       1024,       1024,     1024,     8192, 0xe6d9ec37
-0,       2048,       2048,     1024,     8192, 0x5edfea64
-0,       3072,       3072,     1024,     8192, 0x7f7be38c
-0,       4096,       4096,     1024,     8192, 0x3f60f5c9
-0,       5120,       5120,     1024,     8192, 0xcee4fe06
-0,       6144,       6144,     1024,     8192, 0xdb98fa3e
-0,       7168,       7168,     1024,     8192, 0x4cb30687
-0,       8192,       8192,     1024,     8192, 0x00f6ecab
-0,       9216,       9216,     1024,     8192, 0xa7b0e0db
-0,      10240,      10240,     1024,     8192, 0xc2dcf89c
-0,      11264,      11264,     1024,     8192, 0x30d6f2fe
-0,      12288,      12288,     1024,     8192, 0xf83ae182
-0,      13312,      13312,     1024,     8192, 0xeecd05d1
-0,      14336,      14336,     1024,     8192, 0xfd3b0559
-0,      15360,      15360,     1024,     8192, 0xcd69e3e6
-0,      16384,      16384,     1024,     8192, 0xdf80fc29
-0,      17408,      17408,     1024,     8192, 0x7e8bf52b
-0,      18432,      18432,     1024,     8192, 0xee07e5f7
-0,      19456,      19456,     1024,     8192, 0xc874f294
+#channel_layout_name 0: 2 channels
+0,          0,          0,     1024,     4096, 0x7bd6fc44
+0,       1024,       1024,     1024,     4096, 0xed38ec37
+0,       2048,       2048,     1024,     4096, 0x4696ea64
+0,       3072,       3072,     1024,     4096, 0xf2c8e38c
+0,       4096,       4096,     1024,     4096, 0x9aa8f5c9
+0,       5120,       5120,     1024,     4096, 0xfb46fe06
+0,       6144,       6144,     1024,     4096, 0x6700fa3e
+0,       7168,       7168,     1024,     4096, 0x235e0687
+0,       8192,       8192,     1024,     4096, 0x8b9aecab
+0,       9216,       9216,     1024,     4096, 0x62f3e0db
+0,      10240,      10240,     1024,     4096, 0xe59ef89c
+0,      11264,      11264,     1024,     4096, 0x1a48f2fe
+0,      12288,      12288,     1024,     4096, 0x9026e182
+0,      13312,      13312,     1024,     4096, 0xec4d05d1
+0,      14336,      14336,     1024,     4096, 0x7ee70559
+0,      15360,      15360,     1024,     4096, 0x807ae3e6
+0,      16384,      16384,     1024,     4096, 0xf0d2fc29
+0,      17408,      17408,     1024,     4096, 0xd9e7f52b
+0,      18432,      18432,     1024,     4096, 0x0f1ce5f7
+0,      19456,      19456,     1024,     4096, 0x6b3cf294
diff --git a/tests/ref/fate/filter-pan-stereo4 b/tests/ref/fate/filter-pan-upmix1
similarity index 100%
copy from tests/ref/fate/filter-pan-stereo4
copy to tests/ref/fate/filter-pan-upmix1
diff --git a/tests/ref/fate/filter-pan-upmix2 b/tests/ref/fate/filter-pan-upmix2
new file mode 100644
index 0000000..56db1c1
--- /dev/null
+++ b/tests/ref/fate/filter-pan-upmix2
@@ -0,0 +1,26 @@
+#tb 0: 1/44100
+#media_type 0: audio
+#codec_id 0: pcm_s16le
+#sample_rate 0: 44100
+#channel_layout 0: 0
+#channel_layout_name 0: 9 channels
+0,          0,          0,      512,     9216, 0xd561bb2b
+0,        512,        512,      512,     9216, 0x591805f9
+0,       1024,       1024,      512,     9216, 0xd46fecd6
+0,       1536,       1536,      512,     9216, 0x1e1f176b
+0,       2048,       2048,      512,     9216, 0xe383f1a6
+0,       2560,       2560,      512,     9216, 0xc628c661
+0,       3072,       3072,      512,     9216, 0x1ad09914
+0,       3584,       3584,      512,     9216, 0x798533cc
+0,       4096,       4096,      512,     9216, 0x4913d581
+0,       4608,       4608,      512,     9216, 0x59f506b3
+0,       5120,       5120,      512,     9216, 0x8885fa28
+0,       5632,       5632,      512,     9216, 0x769ffa95
+0,       6144,       6144,      512,     9216, 0xc636cc46
+0,       6656,       6656,      512,     9216, 0x4740f34b
+0,       7168,       7168,      512,     9216, 0x00d2de28
+0,       7680,       7680,      512,     9216, 0x704a07fc
+0,       8192,       8192,      512,     9216, 0x54a4f682
+0,       8704,       8704,      512,     9216, 0xd6dac181
+0,       9216,       9216,      512,     9216, 0xfcd6fe28
+0,       9728,       9728,      512,     9216, 0x5c41cbdc
