diff --git a/src/main.c b/src/main.c
index ecd6b43..3cb7bad 100644
--- a/src/main.c
+++ b/src/main.c
@@ -241,8 +241,8 @@ static void lo_generate_phase(uint32_t *buf, size_t len, uint32_t step, uint32_t
 
 static void rx_lo_init(double freq)
 {
-	double frac = (double)CLK_SYS_HZ / (8 << LO_BITS_DEPTH);
-	freq = roundf(freq / frac) * frac;
+	double n = round(freq * (8 << LO_BITS_DEPTH) / CLK_SYS_HZ);
+	freq = n * CLK_SYS_HZ / (8 << LO_BITS_DEPTH);
 	uint32_t step = freq * 4294967296.0 / CLK_SYS_HZ;
 	lo_generate_phase(lo_cos, LO_WORDS, step, COS_PHASE);
 	lo_generate_phase(lo_sin, LO_WORDS, step, SIN_PHASE);
@@ -565,7 +565,7 @@ static void do_rx()
 			fwrite(block, IQ_BLOCK_LEN, 1, stdout);
 			fflush(stdout);
 		} else {
-			sleep_us(1);
+			sleep_us(10);
 		}
 	}