2 files changed, 11 insertions, 3 deletions
diff --git a/src/portable/st/stm32_fsdev/dcd_stm32_fsdev.c b/src/portable/st/stm32_fsdev/dcd_stm32_fsdev.c
index 3762b33f9..a6c8d2453 100644
--- a/src/portable/st/stm32_fsdev/dcd_stm32_fsdev.c
+++ b/src/portable/st/stm32_fsdev/dcd_stm32_fsdev.c
@@ -277,7 +277,11 @@ static void handle_ctr_tx(uint32_t ep_id) {
       return;
     }
     xfer->iso_in_sending = false;
+#if FSDEV_USE_SBUF_ISO == 0
     uint8_t buf_id = (ep_reg & USB_EP_DTOG_TX) ? 0 : 1;
+#else
+    uint8_t buf_id = BTABLE_BUF_TX;
+#endif
     btable_set_count(ep_id, buf_id, 0);
   }
 
@@ -758,7 +762,12 @@ static bool edpt_xfer(uint8_t rhport, uint8_t ep_num, tusb_dir_t dir) {
 
     uint16_t cnt = tu_min16(xfer->total_len, xfer->max_packet_size);
 
-    if (ep_is_iso(ep_reg)) {
+#if FSDEV_USE_SBUF_ISO == 0
+    bool const dbl_buf = ep_is_iso(ep_reg);
+#else
+    bool const dbl_buf = false;
+#endif
+    if (dbl_buf) {
       btable_set_rx_bufsize(ep_idx, 0, cnt);
       btable_set_rx_bufsize(ep_idx, 1, cnt);
     } else {
diff --git a/src/portable/st/stm32_fsdev/fsdev_stm32.h b/src/portable/st/stm32_fsdev/fsdev_stm32.h
index 71370b189..4b7d3d301 100644
--- a/src/portable/st/stm32_fsdev/fsdev_stm32.h
+++ b/src/portable/st/stm32_fsdev/fsdev_stm32.h
@@ -202,8 +202,7 @@
   #include "stm32u0xx.h"
   #define FSDEV_PMA_SIZE (1024u)
   #define FSDEV_BUS_32BIT
-  // Disable SBUF_ISO on U0 for now due to bad performance (audio glitching)
-  #define FSDEV_HAS_SBUF_ISO 0
+  #define FSDEV_HAS_SBUF_ISO 1
   #define USB USB_DRD_FS
 
   #define USB_EP_CTR_RX USB_EP_VTRX