diff --git a/main.c b/main.c
index 6405c768..b1379565 100644
--- a/main.c
+++ b/main.c
@@ -102,7 +102,7 @@ int main(int argc, char * argv[]) {
   pclose(gpiod);
   gpiod = popen("pigs m 19 5", "r");		// set PWM audio utput to GPIO 19 (pin 35)
   pclose(gpiod);	
-  gpiod = popen("pigs hc 13 12880000", "r");		// set clock to 12.88 MHz on GPIO 13 (pin 33)
+  gpiod = popen("pigs hc 6 12880000", "r");		// set clock to 12.88 MHz on GPIO 6 (pin 31)
   pclose(gpiod);	
 	
 //  FILE * rpitx_stop = popen("sudo systemctl stop rpitx", "r");