diff --git a/platform/samd11_vcp/dap_config.h b/platform/samd11_vcp/dap_config.h
index bbf2f54..e40ef47 100644
--- a/platform/samd11_vcp/dap_config.h
+++ b/platform/samd11_vcp/dap_config.h
@@ -58,11 +58,11 @@
 #define DAP_CONFIG_PERFORMANCE_ATTR    __attribute__((section(".ramfunc")))
 
 // A value at which dap_clock_test() produces 1 kHz output on the SWCLK pin
-#define DAP_CONFIG_DELAY_CONSTANT      3400
+#define DAP_CONFIG_DELAY_CONSTANT      7700
 
 // A threshold for switching to fast clock (no added delays)
 // This is the frequency produced by dap_clock_test(1) on the SWCLK pin
-#define DAP_CONFIG_FAST_CLOCK          2200000 // Hz
+#define DAP_CONFIG_FAST_CLOCK          2400000 // Hz
 
 /*- Prototypes --------------------------------------------------------------*/
 extern char usb_serial_number[16];