diff --git a/default_presets/V4 Factory Presets.piBank b/default_presets/V4 Factory Presets.piBank
new file mode 100644
index 0000000..5b59a8b
Binary files /dev/null and b/default_presets/V4 Factory Presets.piBank differ
diff --git a/default_presets/build_factory_presets.sh b/default_presets/build_factory_presets.sh
index 218a377..933d140 100755
--- a/default_presets/build_factory_presets.sh
+++ b/default_presets/build_factory_presets.sh
@@ -1,5 +1,5 @@
 #!/usr/bin/bash
-export SRC_ZIP="V3 Factory Presets.piBank"
+export SRC_ZIP="V4 Factory Presets.piBank"
 export DST_ZIP="Factory Presets.piBank"
 
 rm "presets/$DST_ZIP"
diff --git a/default_presets/presets/Factory Presets.piBank b/default_presets/presets/Factory Presets.piBank
index 34f07de..a48181f 100644
Binary files a/default_presets/presets/Factory Presets.piBank and b/default_presets/presets/Factory Presets.piBank differ
diff --git a/default_presets/presets/banks.versionInfo b/default_presets/presets/banks.versionInfo
index 00750ed..b8626c4 100644
--- a/default_presets/presets/banks.versionInfo
+++ b/default_presets/presets/banks.versionInfo
@@ -1 +1 @@
-3
+4
diff --git a/src/Banks.hpp b/src/Banks.hpp
index 550bb78..4576623 100644
--- a/src/Banks.hpp
+++ b/src/Banks.hpp
@@ -188,6 +188,18 @@ namespace pipedal
             }
             return false;
         }
+
+        BankFileEntry* getPresetByName(const std::string&presetName) {
+            for (std::unique_ptr<BankFileEntry> &preset: presets_) 
+            {
+                if (preset->preset().name() == presetName)
+                {
+                    return &(*preset);
+                }
+            }
+            return nullptr;
+        }
+
         bool renamePreset(int64_t instanceId, const std::string &name)
         {
             if (hasName(name))
diff --git a/src/Storage.cpp b/src/Storage.cpp
index e924191..7b8c981 100644
--- a/src/Storage.cpp
+++ b/src/Storage.cpp
@@ -294,8 +294,33 @@ void Storage::MoveExistingFactoryPresetsBank()
 
 namespace pipedal::implementation {
     extern  int64_t ImportBankFile(PiPedalModel &model, const std::filesystem::path& filePath,uint64_t uploadAfter = -1);
+    extern void UpgradeBank(
+        PiPedalModel&model,
+        const std::filesystem::path &existingBankFile,
+        const std::filesystem::path &piBank,
+        const std::vector<std::string>&presetsToUpgrade
+    );
+
 }
 
+void Storage::UpgradeV3FactoryPresets()
+{
+    std::vector<std::string> presetsToUpgrade = {
+        "Marshall JCM800 + TS9",
+        "Huge Lead 2"
+    };
+
+    fs::path factoryPresetPath = GetBankFileName("Factory Presets");
+
+    UpgradeBank(
+        *this->model,
+        factoryPresetPath, 
+        this->configRoot / "default_presets" / "presets" / "Factory Presets.piBank",
+        presetsToUpgrade
+    );
+
+}   
+
 void Storage::InstallFactoryPresets() 
 {
     fs::path defaultBankFilePath =  this->configRoot / "default_presets" / "presets" / "Factory Presets.piBank";
@@ -367,14 +392,22 @@ void Storage::ProvisionDefaultBanks()
     
     constexpr uint32_t V2_VERSION_NUMBER = 2; // first to have a Factory Presets
     constexpr uint32_t V3_VERSION_NUMBER = 3; // New A2 Presets, completely replacing the previons version.
+    constexpr uint32_t V4_VERSION_NUMBER = 4; // Fix incorrect Cab IR settings.
 
-    if (varPresetVersion < V3_VERSION_NUMBER) {
+    if (varPresetVersion < V4_VERSION_NUMBER) {
         Lv2Log::info("Installing Factory Presets");
 
         // Move the old factory presets bank out of the way. 
-        MoveExistingFactoryPresetsBank();
-        InstallFactoryPresets();
-        SetVarPresetVersion(V3_VERSION_NUMBER);
+        if (varPresetVersion < V3_VERSION_NUMBER) {
+            MoveExistingFactoryPresetsBank();
+        }
+        if (varPresetVersion == V3_VERSION_NUMBER) 
+        {
+            UpgradeV3FactoryPresets();
+        } else {
+            InstallFactoryPresets();
+        }
+        SetVarPresetVersion(V4_VERSION_NUMBER);
         SaveBankIndex(); // checkpoint.
     }
     // Next time we will have to MERGE factor presets.
diff --git a/src/Storage.hpp b/src/Storage.hpp
index 9001748..63e93ad 100644
--- a/src/Storage.hpp
+++ b/src/Storage.hpp
@@ -86,6 +86,7 @@ private:
     void SetVarPresetVersion(int32_t version);
     void UpgradeV1FactoryPresets();
     void MoveExistingFactoryPresetsBank();
+    void UpgradeV3FactoryPresets();
     void InstallFactoryPresets();
     void CopyFactoryPresetsToDefaultBank();
     void ProvisionDefaultBanks();
diff --git a/src/WebServerConfig.cpp b/src/WebServerConfig.cpp
index 094c7a6..4d33bc4 100644
--- a/src/WebServerConfig.cpp
+++ b/src/WebServerConfig.cpp
@@ -183,6 +183,67 @@ static fs::path GetTone3000ThumbnailFile(const fs::path& thumbnailDirectory, con
 
 namespace pipedal::implementation {
 
+    void UpgradeBank(PiPedalModel& model,
+        const std::filesystem::path& existingBankFilePath,
+        const std::filesystem::path& piBankFilePath,
+        const std::vector<std::string>& presetsToUpgrade
+    ) {
+        BankFile sourceBankFile;
+
+
+        if (piBankFilePath.empty())
+        {
+            throw std::runtime_error("Unexpected.");
+        }
+        if (IsZipFile(piBankFilePath))
+        {
+            auto presetReader = PresetBundleReader::LoadPresetsFile(model, piBankFilePath);
+            presetReader->ExtractMediaFiles();
+
+            std::stringstream ss(presetReader->GetPresetJson());
+            json_reader reader(ss);
+            reader.read(&sourceBankFile);
+        }
+        else
+        {
+            std::ifstream f{ piBankFilePath };
+            if (!f.is_open()) {
+                throw std::runtime_error(SS("Unable to open file " << piBankFilePath));
+            }
+            // legacy json format, no zip, no media files.
+            json_reader reader(f);
+            reader.read(&sourceBankFile);
+        }
+
+        BankFile existingBankFile;
+        {
+            std::ifstream ifs{ existingBankFilePath };
+            if (!ifs.is_open()) {
+                return;
+            }
+            json_reader reader{ ifs };
+            reader.read(&existingBankFile);
+        }
+
+        for (const std::string& presetToUpgrade : presetsToUpgrade)
+        {
+            BankFileEntry* existingEntry = existingBankFile.getPresetByName(presetToUpgrade);
+            if (existingEntry) {
+                BankFileEntry* newEntry = sourceBankFile.getPresetByName(presetToUpgrade);
+                if (newEntry)
+                {
+                    existingEntry->preset(newEntry->preset());
+                }
+            }
+        }
+        {
+            std::ofstream ofs{ existingBankFilePath };
+            json_writer writer{ ofs };
+            writer.write(existingBankFile);
+        }
+
+
+    }
     int64_t ImportBankFile(PiPedalModel& model, const std::filesystem::path& filePath, uint64_t uploadAfter = -1)
     {
         BankFile bankFile;
@@ -211,6 +272,7 @@ namespace pipedal::implementation {
             json_reader reader(f);
             reader.read(&bankFile);
         }
+
         uint64_t instanceId = model.UploadBank(bankFile, uploadAfter);
 
         return instanceId;
@@ -623,7 +685,7 @@ public:
                 fs::path path = GetTone3000ThumbnailFile(this->model->Tone3000ThumbnailDirectory(), id);
                 if (!fs::exists(path))
                 {
-                    path = GetTone3000ThumbnailFile(this->model->OldTone3000ThumbnailDirectory(),id);
+                    path = GetTone3000ThumbnailFile(this->model->OldTone3000ThumbnailDirectory(), id);
                     if (!fs::exists(path))
                     {
                         throw PiPedalException("File not found.");