diff --git a/src/libsdr/sdr.c b/src/libsdr/sdr.c
index 32645ab..43e04c7 100644
--- a/src/libsdr/sdr.c
+++ b/src/libsdr/sdr.c
@@ -307,7 +307,7 @@ void *sdr_open(const char __attribute__((__unused__)) *device, double *tx_freque
 			PDEBUG(DSDR, DEBUG_INFO, "We shift center frequency %.0f KHz down (half bandwidth), to prevent channel from overlap with DC level.\n", bandwidth / 2.0 / 1e3);
 		} else {
 			/* find two channels that are aside the center */
-			double low_dist, high_dist, dist;
+			double low_dist = 0, high_dist = 0, dist;
 			int low_c = -1, high_c = -1;
 			for (c = 0; c < channels; c++) {
 				dist = fabs(tx_center_frequency - sdr->chan[c].tx_frequency);