diff --git a/src/StateFileConfig.cxx b/src/StateFileConfig.cxx
index ac54052b1..22788d86e 100644
--- a/src/StateFileConfig.cxx
+++ b/src/StateFileConfig.cxx
@@ -10,7 +10,8 @@
 
 StateFileConfig::StateFileConfig(const ConfigData &config)
 	:path(config.GetPath(ConfigOption::STATE_FILE)),
-	 interval(config.GetUnsigned(ConfigOption::STATE_FILE_INTERVAL,
+	 interval(config.GetDuration(ConfigOption::STATE_FILE_INTERVAL,
+				     std::chrono::seconds{1},
 				     DEFAULT_INTERVAL)),
 	 restore_paused(config.GetBool(ConfigOption::RESTORE_PAUSED, false))
 {
diff --git a/src/config/Data.cxx b/src/config/Data.cxx
index 202f2b674..72da3ba81 100644
--- a/src/config/Data.cxx
+++ b/src/config/Data.cxx
@@ -86,32 +86,17 @@ ConfigData::GetPositive(ConfigOption option, unsigned default_value) const
 }
 
 std::chrono::steady_clock::duration
-ConfigData::GetUnsigned(ConfigOption option,
+ConfigData::GetDuration(ConfigOption option,
+			std::chrono::steady_clock::duration min_value,
 			std::chrono::steady_clock::duration default_value) const
 {
-	return With(option, [default_value](const char *s){
+	return With(option, [min_value, default_value](const char *s){
 		if (s == nullptr)
 			return default_value;
 
 		auto value = ParseDuration(s);
-		if (value < std::chrono::steady_clock::duration{})
-			throw std::runtime_error("Value must not be negative");
-
-		return value;
-	});
-}
-
-std::chrono::steady_clock::duration
-ConfigData::GetPositive(ConfigOption option,
-			std::chrono::steady_clock::duration default_value) const
-{
-	return With(option, [default_value](const char *s){
-		if (s == nullptr)
-			return default_value;
-
-		auto value = ParseDuration(s);
-		if (value <= std::chrono::steady_clock::duration{})
-			throw std::runtime_error("Value must be positive");
+		if (value < min_value)
+			throw std::runtime_error{"Value is too small"};
 
 		return value;
 	});
diff --git a/src/config/Data.hxx b/src/config/Data.hxx
index 7718d71f1..cac7f3f4e 100644
--- a/src/config/Data.hxx
+++ b/src/config/Data.hxx
@@ -60,15 +60,12 @@ struct ConfigData {
 	unsigned GetUnsigned(ConfigOption option,
 			     unsigned default_value) const;
 
-	std::chrono::steady_clock::duration
-	GetUnsigned(ConfigOption option,
-		    std::chrono::steady_clock::duration default_value) const;
-
 	unsigned GetPositive(ConfigOption option,
 			     unsigned default_value) const;
 
 	std::chrono::steady_clock::duration
-	GetPositive(ConfigOption option,
+	GetDuration(ConfigOption option,
+		    std::chrono::steady_clock::duration min_value,
 		    std::chrono::steady_clock::duration default_value) const;
 
 	bool GetBool(ConfigOption option, bool default_value) const;