diff --git a/Jellyfin.Plugin.Jellypod/Channels/JellypodChannel.cs b/Jellyfin.Plugin.Jellypod/Channels/JellypodChannel.cs
index eff9018..5ab64b2 100644
--- a/Jellyfin.Plugin.Jellypod/Channels/JellypodChannel.cs
+++ b/Jellyfin.Plugin.Jellypod/Channels/JellypodChannel.cs
@@ -387,10 +387,9 @@ public class JellypodChannel : IChannel, IHasCacheKey, IRequiresMediaInfoCallbac
     /// <inheritdoc />
     public string? GetCacheKey(string? userId)
     {
-        // Use 5-minute time buckets for cache key
-        var now = DateTime.Now;
-        var timeBucket = new DateTime(now.Year, now.Month, now.Day, now.Hour, (now.Minute / 5) * 5, 0);
-        return timeBucket.ToString("yyyy-MM-dd-HH-mm", CultureInfo.InvariantCulture);
+        // Include database modification time so cache invalidates when podcasts/episodes change
+        var lastModified = _storageService.LastModified;
+        return lastModified.ToString("O", CultureInfo.InvariantCulture);
     }
 
     /// <inheritdoc />
diff --git a/Jellyfin.Plugin.Jellypod/Services/IPodcastStorageService.cs b/Jellyfin.Plugin.Jellypod/Services/IPodcastStorageService.cs
index cb01e09..ac3af64 100644
--- a/Jellyfin.Plugin.Jellypod/Services/IPodcastStorageService.cs
+++ b/Jellyfin.Plugin.Jellypod/Services/IPodcastStorageService.cs
@@ -10,6 +10,12 @@ namespace Jellyfin.Plugin.Jellypod.Services;
 /// </summary>
 public interface IPodcastStorageService
 {
+    /// <summary>
+    /// Gets the cached last modification time (synchronous, for cache key generation).
+    /// Returns default if database hasn't been loaded yet.
+    /// </summary>
+    DateTime LastModified { get; }
+
     /// <summary>
     /// Gets all subscribed podcasts.
     /// </summary>
@@ -57,4 +63,10 @@ public interface IPodcastStorageService
     /// </summary>
     /// <returns>The base path for podcast storage.</returns>
     string GetStoragePath();
+
+    /// <summary>
+    /// Gets the last time the database was modified.
+    /// </summary>
+    /// <returns>The last modification time, or null if unknown.</returns>
+    Task<DateTime?> GetLastModifiedAsync();
 }
diff --git a/Jellyfin.Plugin.Jellypod/Services/PodcastStorageService.cs b/Jellyfin.Plugin.Jellypod/Services/PodcastStorageService.cs
index 249f2c4..129db9d 100644
--- a/Jellyfin.Plugin.Jellypod/Services/PodcastStorageService.cs
+++ b/Jellyfin.Plugin.Jellypod/Services/PodcastStorageService.cs
@@ -28,6 +28,7 @@ public sealed class PodcastStorageService : IPodcastStorageService, IDisposable
     private readonly IApplicationPaths _applicationPaths;
     private readonly SemaphoreSlim _dbLock = new(1, 1);
     private PodcastDatabase? _cache;
+    private DateTime _lastModified;
 
     /// <summary>
     /// Initializes a new instance of the <see cref="PodcastStorageService"/> class.
@@ -47,6 +48,9 @@ public sealed class PodcastStorageService : IPodcastStorageService, IDisposable
         "Jellypod",
         "podcasts.json");
 
+    /// <inheritdoc />
+    public DateTime LastModified => _lastModified;
+
     /// <inheritdoc />
     public async Task<IReadOnlyList<Podcast>> GetAllPodcastsAsync()
     {
@@ -180,6 +184,7 @@ public sealed class PodcastStorageService : IPodcastStorageService, IDisposable
         {
             _logger.LogWarning("Database file does not exist at {Path}", DatabasePath);
             _cache = new PodcastDatabase();
+            _lastModified = DateTime.UtcNow;
             return _cache;
         }
 
@@ -189,6 +194,7 @@ public sealed class PodcastStorageService : IPodcastStorageService, IDisposable
             var json = await File.ReadAllTextAsync(DatabasePath).ConfigureAwait(false);
             _logger.LogInformation("Read {Length} characters from database file", json.Length);
             _cache = JsonSerializer.Deserialize<PodcastDatabase>(json, JsonOptions) ?? new PodcastDatabase();
+            _lastModified = _cache.LastSaved;
             _logger.LogInformation("Loaded {Count} podcasts from database", _cache.Podcasts.Count);
             return _cache;
         }
@@ -196,6 +202,7 @@ public sealed class PodcastStorageService : IPodcastStorageService, IDisposable
         {
             _logger.LogError(ex, "Failed to load podcast database, starting fresh");
             _cache = new PodcastDatabase();
+            _lastModified = DateTime.UtcNow;
             return _cache;
         }
     }
@@ -211,6 +218,7 @@ public sealed class PodcastStorageService : IPodcastStorageService, IDisposable
             }
 
             db.LastSaved = DateTime.UtcNow;
+            _lastModified = db.LastSaved;
             var json = JsonSerializer.Serialize(db, JsonOptions);
             await File.WriteAllTextAsync(DatabasePath, json).ConfigureAwait(false);
             _cache = db;
@@ -261,6 +269,13 @@ public sealed class PodcastStorageService : IPodcastStorageService, IDisposable
         return ".mp3";
     }
 
+    /// <inheritdoc />
+    public async Task<DateTime?> GetLastModifiedAsync()
+    {
+        var db = await LoadDatabaseAsync().ConfigureAwait(false);
+        return db.LastSaved;
+    }
+
     /// <inheritdoc />
     public void Dispose()
     {