diff --git a/dns/enhancer.go b/dns/enhancer.go
index 76d4460e..ab144fd3 100644
--- a/dns/enhancer.go
+++ b/dns/enhancer.go
@@ -109,7 +109,7 @@ func NewEnhancer(cfg Config) *ResolverEnhancer {
 
 	if cfg.EnhancedMode != C.DNSNormal {
 		fakePool = cfg.Pool
-		mapping = cache.New(cache.WithSize[netip.Addr, string](4096), cache.WithStale[netip.Addr, string](true))
+		mapping = cache.New(cache.WithSize[netip.Addr, string](4096))
 	}
 
 	return &ResolverEnhancer{
diff --git a/dns/middleware.go b/dns/middleware.go
index f2dd9c96..695432da 100644
--- a/dns/middleware.go
+++ b/dns/middleware.go
@@ -129,6 +129,10 @@ func withMapping(mapping *cache.LruCache[netip.Addr, string]) middleware {
 					continue
 				}
 
+				if ttl < 1 {
+					ttl = 1
+				}
+
 				mapping.SetWithExpire(ip, host, time.Now().Add(time.Second*time.Duration(ttl)))
 			}