diff --git a/examples/device/audio_4_channel_mic/CMakeLists.txt b/examples/device/audio_4_channel_mic/CMakeLists.txt
index ae6bf0142..0f5d36193 100644
--- a/examples/device/audio_4_channel_mic/CMakeLists.txt
+++ b/examples/device/audio_4_channel_mic/CMakeLists.txt
@@ -23,18 +23,16 @@ target_sources(${PROJECT} PUBLIC
   ${CMAKE_CURRENT_SOURCE_DIR}/src/usb_descriptors.c
   )
 
-# CMSIS sources
-target_sources(${PROJECT} PUBLIC
-  ${TOP}/lib/CMSIS_5/CMSIS/DSP/Source/CommonTables/arm_common_tables.c
-  ${TOP}/lib/CMSIS_5/CMSIS/DSP/Source/FastMathFunctions/arm_sin_q15.c
-  )
-
 # Example include
 target_include_directories(${PROJECT} PUBLIC
   ${CMAKE_CURRENT_SOURCE_DIR}/src
-  ${TOP}/lib/CMSIS_5/CMSIS/DSP/Include
   )
 
+# Add libm for GCC
+if (CMAKE_C_COMPILER_ID STREQUAL "GNU")
+  target_link_libraries(${PROJECT} PUBLIC m)
+endif()
+
 # Configure compilation flags and libraries for the example without RTOS.
 # See the corresponding function in hw/bsp/FAMILY/family.cmake for details.
 family_configure_device_example(${PROJECT} noos)
diff --git a/examples/device/audio_4_channel_mic/Makefile b/examples/device/audio_4_channel_mic/Makefile
index 97e4118c0..8ee6a01ec 100644
--- a/examples/device/audio_4_channel_mic/Makefile
+++ b/examples/device/audio_4_channel_mic/Makefile
@@ -3,18 +3,12 @@ include ../../make.mk
 INC += \
   src \
   $(TOP)/hw \
-  $(TOP)/lib/CMSIS_5/CMSIS/DSP/Include \
 
 # Example source
 EXAMPLE_SOURCE += \
   src/main.c \
   src/usb_descriptors.c \
 
-# CMSIS sources
-SRC_C += \
-  lib/CMSIS_5/CMSIS/DSP/Source/CommonTables/arm_common_tables.c \
-  lib/CMSIS_5/CMSIS/DSP/Source/FastMathFunctions/arm_sin_q15.c \
-
 SRC_C += $(addprefix $(CURRENT_PATH)/, $(EXAMPLE_SOURCE))
 
 include ../../rules.mk
diff --git a/examples/device/audio_4_channel_mic/skip.txt b/examples/device/audio_4_channel_mic/skip.txt
index 1ee86a485..3c42a96d9 100644
--- a/examples/device/audio_4_channel_mic/skip.txt
+++ b/examples/device/audio_4_channel_mic/skip.txt
@@ -1,3 +1,4 @@
 mcu:SAMD11
 mcu:SAME5X
 mcu:SAMG
+family:broadcom_64bit
diff --git a/examples/device/audio_4_channel_mic/src/main.c b/examples/device/audio_4_channel_mic/src/main.c
index 3b21b4ac6..4bcbdb692 100644
--- a/examples/device/audio_4_channel_mic/src/main.c
+++ b/examples/device/audio_4_channel_mic/src/main.c
@@ -34,7 +34,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
-#include "arm_math.h"
+#include <math.h>
 
 #include "bsp/board_api.h"
 #include "tusb.h"
@@ -96,6 +96,27 @@ int main(void)
   sampleFreqRng.subrange[0].bMax = AUDIO_SAMPLE_RATE;
   sampleFreqRng.subrange[0].bRes = 0;
 
+  // Generate dummy data
+  uint16_t * p_buff = i2s_dummy_buffer[0];
+  uint16_t dataVal = 1;
+  for (uint16_t cnt = 0; cnt < AUDIO_SAMPLE_RATE/1000; cnt++)
+  {
+    // CH0 saw wave
+    *p_buff++ = dataVal;
+    // CH1 inverted saw wave
+    *p_buff++ = 60 + AUDIO_SAMPLE_RATE/1000 - dataVal;
+    dataVal++;
+  }
+  p_buff = i2s_dummy_buffer[1];
+  for (uint16_t cnt = 0; cnt < AUDIO_SAMPLE_RATE/1000; cnt++)
+  {
+    // CH3 square wave
+    *p_buff++ = cnt < (AUDIO_SAMPLE_RATE/1000/2) ? 120:170;
+    // CH4 sinus wave
+    float t = 2*3.1415f * cnt / (AUDIO_SAMPLE_RATE/1000);
+    *p_buff++ = (uint16_t)(sinf(t) * 25) + 200;
+  }
+
   while (1)
   {
     tud_task(); // tinyusb device task
@@ -399,7 +420,16 @@ bool tud_audio_tx_done_pre_load_cb(uint8_t rhport, uint8_t itf, uint8_t ep_in, u
   (void) ep_in;
   (void) cur_alt_setting;
 
-  // Write buffer[0] (CH0-1) and buffer[1] (CH1-2) into FIFO
+
+  // In read world application data flow is driven by I2S clock,
+  // both tud_audio_tx_done_pre_load_cb() & tud_audio_tx_done_post_load_cb() are hardly used.
+  // For example in your I2S receive callback:
+  // void I2S_Rx_Callback(int channel, const void* data, uint16_t samples)
+  // {
+  //    tud_audio_write_support_ff(channel, data, samples * N_BYTES_PER_SAMPLE * N_CHANNEL_PER_FIFO);
+  // }
+
+  // Write I2S buffer into FIFO
   for (uint8_t cnt=0; cnt < 2; cnt++)
   {
     tud_audio_write_support_ff(cnt, i2s_dummy_buffer[cnt], AUDIO_SAMPLE_RATE/1000 * CFG_TUD_AUDIO_FUNC_1_N_BYTES_PER_SAMPLE_TX * CFG_TUD_AUDIO_FUNC_1_CHANNEL_PER_FIFO_TX);
@@ -416,27 +446,6 @@ bool tud_audio_tx_done_post_load_cb(uint8_t rhport, uint16_t n_bytes_copied, uin
   (void) ep_in;
   (void) cur_alt_setting;
 
-  // Generate dummy data
-  uint16_t * p_buff = i2s_dummy_buffer[0];
-  uint16_t dataVal = 1;
-  for (uint16_t cnt = 0; cnt < AUDIO_SAMPLE_RATE/1000; cnt++)
-  {
-    // CH0 saw wave
-    *p_buff++ = dataVal;
-    // CH1 inverted saw wave
-    *p_buff++ = 60 + AUDIO_SAMPLE_RATE/1000 - dataVal;
-    dataVal++;
-  }
-  p_buff = i2s_dummy_buffer[1];
-  for (uint16_t cnt = 0; cnt < AUDIO_SAMPLE_RATE/1000; cnt++)
-  {
-    // CH3 square wave
-    *p_buff++ = cnt < (AUDIO_SAMPLE_RATE/1000/2) ? 120:170;
-    // CH4 sinus wave
-    q15_t t = 0x7FFF * cnt / (AUDIO_SAMPLE_RATE/1000);
-    *p_buff++ = arm_sin_q15(t) / 1300 + 200;
-  }
-
   return true;
 }
 
diff --git a/tools/get_deps.py b/tools/get_deps.py
index 8eea3e6de..1fac291a3 100644
--- a/tools/get_deps.py
+++ b/tools/get_deps.py
@@ -166,9 +166,8 @@ deps_optional = {
                             'ch32v307'],
     'lib/CMSIS_5': ['https://github.com/ARM-software/CMSIS_5.git',
                     '20285262657d1b482d132d20d755c8c330d55c1f',
-                    'imxrt kinetis_k32l2 kinetis_kl lpc11 lpc13 lpc15 lpc17 lpc18 lpc40'
-                    'lpc43 lpc51 lpc54 lpc55 mcx mm32 msp432e4 nrf ra saml2x rp2040'
-                    'stm32f0 stm32f1 stm32f2 stm32f3 stm32f4 stm32f7 stm32g0 stm32g4'
+                    'imxrt kinetis_k32l2 kinetis_kl lpc51 lpc54 lpc55 mcx mm32 msp432e4 nrf ra saml2x'
+                    'stm32f0 stm32f1 stm32f2 stm32f3 stm32f4 stm32f7 stm32g0 stm32g4 '
                     'stm32h7 stm32l0 stm32l1 stm32l4 stm32l5 stm32u5 stm32wb'],
     'lib/sct_neopixel': ['https://github.com/gsteiert/sct_neopixel.git',
                          'e73e04ca63495672d955f9268e003cffe168fcd8',