diff --git a/docs/kiss_modem_protocol.md b/docs/kiss_modem_protocol.md
index 5eb09738..5075cf4c 100644
--- a/docs/kiss_modem_protocol.md
+++ b/docs/kiss_modem_protocol.md
@@ -227,7 +227,7 @@ All values little-endian.
 |-------------|---------|-----------------------|
 | Noise floor | 2 bytes | int16_t, dBm (signed) |
 
-The modem recalibrates the noise floor every 2 seconds. AGC resets follow the configured AGC reset interval (default 30 seconds).
+The modem recalibrates the noise floor every 2 seconds. AGC resets follow the configured AGC reset interval (default 32 seconds).
 
 ### Capabilities (Capabilities response)
 
@@ -256,7 +256,7 @@ All values little-endian.
 
 The modem periodically resets the radio's AGC while idle (no transmission in progress and host output not backed up). The interval has 4-second resolution, matching the MeshCore `agc.reset.interval` setting: requested values are rounded down to a multiple of 4, so 1-3 disable the reset. Values above 1020 return `InvalidParam`. SetAgcResetInterval replies with the AgcResetInterval response carrying the effective value, and restarts the countdown from the time of the request.
 
-The default is 30 seconds. The setting is not persisted; hosts should re-send it after reconnecting or rebooting the modem.
+The default is 32 seconds (previously a fixed 30; changed so the default is a settable 4-second multiple). The setting is not persisted; hosts should re-send it after reconnecting or rebooting the modem.
 
 ### FEM State (SetFemState / FemState response)
 
diff --git a/examples/kiss_modem/KissModem.h b/examples/kiss_modem/KissModem.h
index 24021bdb..bee41634 100644
--- a/examples/kiss_modem/KissModem.h
+++ b/examples/kiss_modem/KissModem.h
@@ -106,7 +106,7 @@
 /* FEM requests are answered strictly in arrival order; this many may wait (e.g. during a TX) */
 #define KISS_FEM_OP_QUEUE_DEPTH  4
 
-#define KISS_AGC_RESET_DEFAULT_SEC 30
+#define KISS_AGC_RESET_DEFAULT_SEC 32  // a multiple of the 4 s step, so hosts can set it back
 #define KISS_AGC_RESET_MAX_SEC     1020
 #define KISS_AGC_RESET_STEP_SEC    4
 
diff --git a/test/test_kiss_modem/test_hw_controls.cpp b/test/test_kiss_modem/test_hw_controls.cpp
index e0fdd729..2b0b779e 100644
--- a/test/test_kiss_modem/test_hw_controls.cpp
+++ b/test/test_kiss_modem/test_hw_controls.cpp
@@ -208,8 +208,11 @@ TEST_F(KissHwControlTest, CapabilitiesReflectBoardFem) {
   EXPECT_EQ(hw1({HW_CMD_GET_CAPABILITIES}), (std::vector<uint8_t>{0x9B, 0x07, 0x00, 0x00, 0x00}));
 }
 
-TEST_F(KissHwControlTest, AgcIntervalDefaultsToThirtySeconds) {
-  EXPECT_EQ(hw1({HW_CMD_GET_AGC_RESET_INTERVAL}), (std::vector<uint8_t>{0x9D, 30, 0}));
+TEST_F(KissHwControlTest, AgcIntervalDefaultsToThirtyTwoSeconds) {
+  EXPECT_EQ(hw1({HW_CMD_GET_AGC_RESET_INTERVAL}), (std::vector<uint8_t>{0x9D, 32, 0}));
+  // the default must be restorable, i.e. a multiple of the 4 s step
+  EXPECT_EQ(hw1({HW_CMD_SET_AGC_RESET_INTERVAL, 4, 0}), (std::vector<uint8_t>{0x9D, 4, 0}));
+  EXPECT_EQ(hw1({HW_CMD_SET_AGC_RESET_INTERVAL, KISS_AGC_RESET_DEFAULT_SEC, 0}), (std::vector<uint8_t>{0x9D, KISS_AGC_RESET_DEFAULT_SEC, 0}));
 }
 
 TEST_F(KissHwControlTest, AgcIntervalSetReturnsEffectiveRoundedValue) {
@@ -223,15 +226,15 @@ TEST_F(KissHwControlTest, AgcIntervalSetReturnsEffectiveRoundedValue) {
 TEST_F(KissHwControlTest, AgcIntervalRejectsOutOfRangeAndShortPayload) {
   EXPECT_EQ(hw1({HW_CMD_SET_AGC_RESET_INTERVAL, 0xFD, 0x03}), (std::vector<uint8_t>{HW_RESP_ERROR, HW_ERR_INVALID_PARAM}));
   EXPECT_EQ(hw1({HW_CMD_SET_AGC_RESET_INTERVAL, 4}), (std::vector<uint8_t>{HW_RESP_ERROR, HW_ERR_INVALID_LENGTH}));
-  EXPECT_EQ(hw1({HW_CMD_GET_AGC_RESET_INTERVAL}), (std::vector<uint8_t>{0x9D, 30, 0}));
+  EXPECT_EQ(hw1({HW_CMD_GET_AGC_RESET_INTERVAL}), (std::vector<uint8_t>{0x9D, 32, 0}));
 }
 
 TEST_F(KissHwControlTest, AgcResetsOnDefaultSchedule) {
-  advance(29999);
+  advance(31999);
   EXPECT_EQ(radio.agc_resets, 0);
   advance(1);
   EXPECT_EQ(radio.agc_resets, 1);
-  advance(29999);
+  advance(31999);
   EXPECT_EQ(radio.agc_resets, 1);
   advance(1);
   EXPECT_EQ(radio.agc_resets, 2);