diff -aur SDK_10.0.10.118/sdk/bsp/peripherals/src/hw_usb_da1469x.c ../build/extbld/third_party/bsp/dialog/da14695/sdk/SDK_10.0.10.118/sdk/bsp/peripherals/src/hw_usb_da1469x.c
--- SDK_10.0.10.118/sdk/bsp/peripherals/src/hw_usb_da1469x.c	2019-12-20 11:51:02.000000000 +0300
+++ ../build/extbld/third_party/bsp/dialog/da14695/sdk/SDK_10.0.10.118/sdk/bsp/peripherals/src/hw_usb_da1469x.c	2020-07-07 14:09:13.935103221 +0300
@@ -22,6 +22,7 @@
 #include "sys_power_mgr.h"
 #include "sys_clock_mgr.h"
 #include "qspi_automode.h"
+#include "util/log.h"
 /*========================== Local macro definitions ========================*/
 
 /*========================== Global definitions =============================*/
@@ -962,6 +963,9 @@
          * To call multiple concurrent USB-TX use queues for the buffers to avoid overwriting.
          * The current implementation is single buffer thus the use of ep->flags.tx_busy flag.
          */
+        if(ep->flags.tx_busy)
+            log_warning("Endpoint %d is busy", ep_nr);
+
         ASSERT_WARNING(ep->flags.tx_busy == 0);
         ep->tx.max_size = size;
         ep->tx.actual_size = 0;
