diff --git a/firmware/drivers/fmradio_i2c.c b/firmware/drivers/fmradio_i2c.c
index 1c9bc300c2..0a1d0c1fd7 100644
--- a/firmware/drivers/fmradio_i2c.c
+++ b/firmware/drivers/fmradio_i2c.c
@@ -80,7 +80,17 @@ int fmradio_i2c_read(unsigned char address, unsigned char* buf, int count)
 #endif
 
 /* delay loop to achieve 400kHz at 120MHz CPU frequency */
-#define DELAY   do { volatile int _x; for(_x=0;_x<22;_x++);} while (0)
+#define DELAY   \
+    ({                                \
+        int _x_;                      \
+        asm volatile (                \
+            "move.l #21, %[_x_] \r\n" \
+        "1:                     \r\n" \
+            "subq.l #1, %[_x_]  \r\n" \
+            "bhi.b  1b          \r\n" \
+            : [_x_]"=&d"(_x_)         \
+        );                            \
+    })
 
 static void fmradio_i2c_start(void)
 {
@@ -102,8 +112,8 @@ static void fmradio_i2c_stop(void)
    SDA_HI;
 }
 
-
-static void fmradio_i2c_ack(void)
+/* Generate ACK or NACK */
+static void fmradio_i2c_ack(bool nack)
 {
     /* Here's the deal. The slave is slow, and sometimes needs to wait
        before it can receive the acknowledge. Therefore it forces the clock
@@ -114,7 +124,11 @@ static void fmradio_i2c_ack(void)
        we have to drive the SCL high repeatedly to simulate a pullup. */
     
     SCL_LO;      /* Set the clock low */
-    SDA_LO;
+
+    if (nack)
+        SDA_HI;
+    else
+        SDA_LO;
     
     SCL_INPUT;   /* Set the clock to input */
     while(!SCL)  /* and wait for the slave to release it */
@@ -248,8 +262,7 @@ int fmradio_i2c_read(int address, unsigned char* buf, int count)
         for (i=count; i>0; i--)
         {
             *buf++ = fmradio_i2c_inb();
-            if (i != 1)
-                fmradio_i2c_ack();
+            fmradio_i2c_ack(i == 1);
         }
     }
     else
@@ -275,7 +288,7 @@ int fmradio_i2c_read(int address, unsigned char* buf, int count)
 #define SCL     (PBDR & 0x0002)
 
 /* arbitrary delay loop */
-#define DELAY   do { volatile int _x; for(_x=0;_x<20;_x++);} while (0)
+#define DELAY   do { int _x; for(_x=0;_x<20;_x++);} while (0)
 
 static void fmradio_i2c_start(void)
 {
@@ -296,7 +309,7 @@ static void fmradio_i2c_stop(void)
 }
 
 
-static void fmradio_i2c_ack(void)
+static void fmradio_i2c_ack(bool nack)
 {
     /* Here's the deal. The slave is slow, and sometimes needs to wait
        before it can receive the acknowledge. Therefore it forces the clock
@@ -304,7 +317,11 @@ static void fmradio_i2c_ack(void)
        high before we release the ack. */
     
     SCL_LO;      /* Set the clock low */
-    SDA_LO;
+
+    if (nack)
+        SDA_HI;
+    else
+        SDA_LO;
     
     SCL_INPUT;   /* Set the clock to input */
     while(!SCL)  /* and wait for the slave to release it */
@@ -416,8 +433,7 @@ int fmradio_i2c_read(int address, unsigned char* buf, int count)
         for (i=count; i>0; i--)
         {
             *buf++ = fmradio_i2c_inb();
-            if (i != 1)
-               fmradio_i2c_ack();
+            fmradio_i2c_ack(i == 1);
         }
     }
     else
diff --git a/firmware/target/coldfire/iriver/h100/adc-h100.c b/firmware/target/coldfire/iriver/h100/adc-h100.c
index a20b1e8d30..fb5afce9f5 100644
--- a/firmware/target/coldfire/iriver/h100/adc-h100.c
+++ b/firmware/target/coldfire/iriver/h100/adc-h100.c
@@ -34,7 +34,17 @@ static unsigned char adcdata[NUM_ADC_CHANNELS];
 #define DI_HI  or_l(0x00200000, &GPIO_OUT)
 
 /* delay loop */
-#define DELAY   do { int _x; for(_x=0;_x<10;_x++) asm volatile ("");} while (0)
+#define DELAY   \
+    ({                               \
+        int _x_;                     \
+        asm volatile (               \
+            "move.l #9, %[_x_] \r\n" \
+        "1:                    \r\n" \
+            "subq.l #1, %[_x_] \r\n" \
+            "bhi.b  1b         \r\n" \
+            : [_x_]"=&d"(_x_)        \
+        );                           \
+    })
 
 unsigned short adc_scan(int channel)
 {
diff --git a/firmware/target/coldfire/iriver/h100/sw_i2c-h100.c b/firmware/target/coldfire/iriver/h100/sw_i2c-h100.c
index 49db2b621d..3b2cdc4042 100644
--- a/firmware/target/coldfire/iriver/h100/sw_i2c-h100.c
+++ b/firmware/target/coldfire/iriver/h100/sw_i2c-h100.c
@@ -42,7 +42,17 @@
 #define SDA_HI     and_l(~0x00002000, &GPIO1_ENABLE)
 
 /* delay loop to achieve 400kHz at 120MHz CPU frequency */
-#define DELAY    do { volatile int _x; for(_x=0;_x<22;_x++);} while(0)
+#define DELAY   \
+    ({                                \
+        int _x_;                      \
+        asm volatile (                \
+            "move.l #21, %[_x_] \r\n" \
+        "1:                     \r\n" \
+            "subq.l #1, %[_x_]  \r\n" \
+            "bhi.b  1b          \r\n" \
+            : [_x_]"=&d"(_x_)         \
+        );                            \
+    })
 
 void sw_i2c_init(void)
 {