diff --git a/src/librtlsdr.c b/src/librtlsdr.c
index b369a5d..4fb2128 100644
--- a/src/librtlsdr.c
+++ b/src/librtlsdr.c
@@ -1565,11 +1565,11 @@ int rtlsdr_open(rtlsdr_dev_t **out_dev, uint32_t index)
 	}
 
 	/* initialise GPIOs */
-	rtlsdr_set_gpio_output(dev, 5);
+	rtlsdr_set_gpio_output(dev, 4);
 
 	/* reset tuner before probing */
-	rtlsdr_set_gpio_bit(dev, 5, 1);
-	rtlsdr_set_gpio_bit(dev, 5, 0);
+	rtlsdr_set_gpio_bit(dev, 4, 1);
+	rtlsdr_set_gpio_bit(dev, 4, 0);
 
 	reg = rtlsdr_i2c_read_reg(dev, FC2580_I2C_ADDR, FC2580_CHECK_ADDR);
 	if ((reg & 0x7f) == FC2580_CHECK_VAL) {