diff --git a/driver/bk4819.c b/driver/bk4819.c
index 8501939..cb6aa2f 100644
--- a/driver/bk4819.c
+++ b/driver/bk4819.c
@@ -613,51 +613,49 @@ void BK4819_SetFilterBandwidth(const BK4819_FilterBandwidth_t Bandwidth, const b
     {
         default:
         case BK4819_FILTER_BW_WIDE: // 25kHz
-            val = (4u << 12) |     // *3 RF filter bandwidth
-                  (6u <<  6) |     // *0 AFTxLPF2 filter Band Width
-                  (2u <<  4) |     //  2 BW Mode Selection
-                  (1u <<  3) |     //  1
-                  (0u <<  2);     //  0 Gain after FM Demodulation
-
             if (weak_no_different) {
                 // make the RX bandwidth the same with weak signals
-                val |= (4u <<  9);     // *0 RF filter bandwidth when signal is weak
+                val = 0x3628; // Old value 0x49a8 < v3.6
             } else {
-                /// with weak RX signals the RX bandwidth is reduced
-                val |= (2u <<  9);     // *0 RF filter bandwidth when signal is weak
+                // with weak RX signals the RX bandwidth is reduced
+                val = 0x3428; // Old value 0x45a8 < v3.6
             }
 
             break;
 
         case BK4819_FILTER_BW_NARROW:   // 12.5kHz
-            val = (4u << 12) |     // *4 RF filter bandwidth
-                  (0u <<  6) |     // *1 AFTxLPF2 filter Band Width
-                  (0u <<  4) |     //  0 BW Mode Selection
-                  (1u <<  3) |     //  1
-                  (0u <<  2);      //  0 Gain after FM Demodulation
-
             if (weak_no_different) {
-                val |= (4u <<  9);     // *0 RF filter bandwidth when signal is weak
+                // make the RX bandwidth the same with weak signals
+                val = 0x3648; // Old value 0x4808 < v3.6
             } else {
-                val |= (2u <<  9);
+                // with weak RX signals the RX bandwidth is reduced
+                val = 0x3448; // Old value 0x4408 < v3.6
             }
 
             break;
 
         case BK4819_FILTER_BW_NARROWER: // 6.25kHz
-            val = (3u << 12) |     //  3 RF filter bandwidth
-                  (3u <<  9) |     // *0 RF filter bandwidth when signal is weak
-                  (1u <<  6) |     //  1 AFTxLPF2 filter Band Width
-                  (1u <<  4) |     //  1 BW Mode Selection
-                  (1u <<  3) |     //  1
-                  (0u <<  2);      //  0 Gain after FM Demodulation
-
             if (weak_no_different) {
-                val |= (3u <<  9);
+                // make the RX bandwidth the same with weak signals
+                val = 0x1348; // Old value 0x3658 < v3.6
             } else {
-                val |= (0u <<  9);     //  0 RF filter bandwidth when signal is weak
+                // with weak RX signals the RX bandwidth is reduced
+                val = 0x1148; // Old value 0x3658 < v3.6
             }
             break;
+
+        /*
+        case BK4819_FILTER_BW_AM:   // 8.33kHz
+            if (weak_no_different) {
+                // make the RX bandwidth the same with weak signals
+                val = 0x4858;
+            } else {
+                // with weak RX signals the RX bandwidth is reduced
+                val = 0x4458;
+            }
+
+            break;
+        */
     }
 
     BK4819_WriteRegister(BK4819_REG_43, val);