diff --git a/kicad/rx/sdrt41-backups/sdrt41-2023-02-01_112022.zip b/kicad/rx/sdrt41-backups/sdrt41-2023-02-01_112022.zip
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diff --git a/kicad/tx/sdrt41-tx-backups/sdrt41-tx-2023-02-01_112059.zip b/kicad/tx/sdrt41-tx-backups/sdrt41-tx-2023-02-01_112059.zip
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diff --git a/si5351.cpp b/si5351.cpp
index a00d126..4f0cf1e 100644
--- a/si5351.cpp
+++ b/si5351.cpp
@@ -140,6 +140,9 @@ void Si5351::reset(void)
 	si5351_write(22, 0x0c);
 	si5351_write(23, 0x0c);
 
+	// set spread spectrum feature is disabled
+	si5351_write(SI5351_SSC_PARAM0, 0);
+
 	// Set PLLA and PLLB to 800 MHz for automatic tuning
 	set_pll(SI5351_PLL_FIXED, SI5351_PLLA);
 	set_pll(SI5351_PLL_FIXED, SI5351_PLLB);