diff --git a/ubb-la/ubb-la.c b/ubb-la/ubb-la.c
index 7a70e8d..7b4750d 100644
--- a/ubb-la/ubb-la.c
+++ b/ubb-la/ubb-la.c
@@ -167,7 +167,8 @@ quit:
 }
 
 
-static void xfers(unsigned long *bufs, int n_bufs, int nibbles)
+static void xfers(unsigned long *bufs, int n_bufs, int nibbles,
+    const struct mmcclk *clk, const struct mmcclk *fast_clk)
 {
 	int i = 0;
 
@@ -194,18 +195,24 @@ static void xfers(unsigned long *bufs, int n_bufs, int nibbles)
 
 		MSC_STRPCL = MSC_STRPCRL_START_OP;
 
+		MSC_CLKRT = fast_clk->clkrt;
+		MSCCDR = 0;
+
 		/*
 		 * Experimental value for 12 MSa/s: hangs always/usually with
 		 * 231 cycles, hangs sometimes with 232, hands never (so far)
 		 * with 233.
 		 */
-		for (j = 0; j != 233; j++) asm volatile ("");
+//		for (j = 0; j != 233; j++) asm volatile ("");
 
 //		while (MSC_STAT & MSC_STAT_DATA_FIFO_EMPTY);
-//		while (!(MSC_STAT & MSC_STAT_END_CMD_RES));
+		while (!(MSC_STAT & MSC_STAT_END_CMD_RES));
 
 		IN(UBB_CMD);
 
+		MSCCDR = clk->clkdiv;
+		MSC_CLKRT = clk->clkrt;
+
 		DCS(DMA) =
 		    DCS_NDES |          /* no descriptor */
 		    DCS_CTE;            /* enable channel */
@@ -291,7 +298,8 @@ static int do_buf(int nibbles, uint32_t trigger, uint32_t mask)
 }
 
 
-static void do_bufs(int n_bufs, int nibbles)
+static void do_bufs(int n_bufs, int nibbles,
+    const struct mmcclk *clk, const struct mmcclk *fast_clk)
 {
 	uint8_t *bufs[n_bufs];
 	struct physmem_vec vecs[n_bufs];
@@ -316,7 +324,8 @@ static void do_bufs(int n_bufs, int nibbles)
 		}
 		addrs[i] = vecs[i].addr;
 	}
-	xfers(addrs, n_bufs, nibbles);
+	assert(!fast_clk->clkdiv);
+	xfers(addrs, n_bufs, nibbles, clk, fast_clk);
 
 	for (i = 0; i != n_bufs; i++)
 		print_samples(stdout, bufs[i], 0, nibbles);
@@ -382,7 +391,7 @@ int main(int argc, char **argv)
 	unsigned long trigger = 1, mask = 0;
 	unsigned long multi = 0;
 	int clkout = 0;
-	struct mmcclk clk;
+	struct mmcclk clk, fast_clk;
 	char *end;
 	int c, res;
 
@@ -442,7 +451,8 @@ int main(int argc, char **argv)
 	if (!multi) {
 		res = !do_buf(8128, trigger, mask);
 	} else {
-		do_bufs(multi, 8128);
+		frequency(&fast_clk, 84e6, 1);
+		do_bufs(multi, 8128, &clk, &fast_clk);
 		res = 0;
 	}