diff --git a/src/index.ts b/src/index.ts
index 15c1486..a514e53 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,4 +1,5 @@
 export * from './netmd';
+export * from './netmd-ekb';
 export * from './netmd-interface';
 export * from './netmd-commands';
 export * from './encrypt-generator';
diff --git a/src/netmd-commands.ts b/src/netmd-commands.ts
index a8e10f0..daafa5c 100644
--- a/src/netmd-commands.ts
+++ b/src/netmd-commands.ts
@@ -1,5 +1,5 @@
 import { NetMD, DevicesIds } from './netmd';
-import { NetMDInterface, Encoding, Channels, TrackFlag, DiscFlag, MDTrack, MDSession, EKBOpenSource, Wireformat } from './netmd-interface';
+import { NetMDInterface, Encoding, Channels, TrackFlag, DiscFlag, MDTrack, MDSession, Wireformat } from './netmd-interface';
 import {
     timeToFrames,
     sanitizeHalfWidthTitle,
@@ -461,7 +461,7 @@ export async function download(
 ) {
     await prepareDownload(mdIface);
 
-    const session = new MDSession(mdIface, new EKBOpenSource());
+    const session = new MDSession(mdIface);
     await session.init();
     const [trk, uuid, ccid] = await session.downloadTrack(track, progressCallback);
 
diff --git a/src/netmd-ekb.ts b/src/netmd-ekb.ts
new file mode 100644
index 0000000..f2656e5
--- /dev/null
+++ b/src/netmd-ekb.ts
@@ -0,0 +1,88 @@
+export interface EKBObject {
+    getLeafId(): string;
+    getRootKey(): Uint8Array;
+    getEKBID(): number;
+    getEKBDataForLeafId(): [Uint8Array[], number, Uint8Array];
+};
+
+export class EKBOpenSource {
+    static getLeafId() {
+        return undefined;
+    }
+
+    getRootKey() {
+        // prettier-ignore
+        return new Uint8Array([
+            0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xf0,
+            0x0f, 0xed, 0xcb, 0xa9, 0x87, 0x65, 0x43, 0x21
+        ])
+    }
+
+    getEKBID() {
+        return 0x26422642;
+    }
+
+    getEKBDataForLeafId(): [Uint8Array[], number, Uint8Array] {
+        // prettier-ignore
+        return [
+            [
+                new Uint8Array([0x25, 0x45, 0x06, 0x4d, 0xea, 0xca, 0x14, 0xf9, 0x96, 0xbd, 0xc8, 0xa4, 0x06, 0xc2, 0x2b, 0x81]),
+                new Uint8Array([0xfb, 0x60, 0xbd, 0xdd, 0x0d, 0xbc, 0xab, 0x84, 0x8a, 0x00, 0x5e, 0x03, 0x19, 0x4d, 0x3e, 0xda]),
+            ],
+            9,
+            new Uint8Array([
+                0x8f, 0x2b, 0xc3, 0x52, 0xe8, 0x6c, 0x5e, 0xd3, 0x06, 0xdc, 0xae, 0x18,
+                0xd2, 0xf3, 0x8c, 0x7f, 0x89, 0xb5, 0xe1, 0x85, 0x55, 0xa1, 0x05, 0xea
+            ])
+        ];
+    }
+}
+
+// EKB generated by Sir68k.
+export class EKBFFOpenSource {
+    static getLeafId() {
+        return 'ffffffff';
+    }
+
+    getRootKey() {
+        // prettier-ignore
+        return new Uint8Array([
+            // 'WMDPWMDPMiniDisc'
+            0x57, 0x4d, 0x44, 0x50, 0x57, 0x4d, 0x44, 0x50,
+            0x4d, 0x69, 0x6e, 0x69, 0x44, 0x69, 0x73, 0x63
+        ])
+    }
+
+    getEKBID() {
+        return 0x13371337;
+    }
+
+    getEKBDataForLeafId(): [Uint8Array[], number, Uint8Array] {
+        // prettier-ignore
+        return [
+            [
+                new Uint8Array([0xb1, 0xd4, 0xaf, 0xfa, 0x80, 0xa0, 0xc9, 0x03, 0xc2, 0x58, 0x4b, 0x1b, 0x44, 0xaf, 0xc4, 0xa6]),
+            ],
+            9,
+
+            new Uint8Array([
+                0x6c, 0x2b, 0xc2, 0x8c, 0x45, 0x2b, 0x54, 0xf1, 0xc3, 0x59, 0x72, 0x3b,
+                0xe3, 0x19, 0x1f, 0x55, 0x17, 0x25, 0x64, 0x0e, 0x65, 0x8c, 0x81, 0x0b
+            ])
+        ];
+    }
+}
+
+// Custom EKB compatibility map
+export const CustomEKBObjects = [
+    { ekb: EKBFFOpenSource, deviceIds: [0x0081, 0x0084] } // SoC: CXD1873, CXD2677
+];
+
+export async function getEKBObject(leafId: string, deviceId: number) {
+    for (const { ekb, deviceIds } of CustomEKBObjects) {
+        if (deviceIds.indexOf(deviceId) >= 0 && ekb.getLeafId() === leafId) {
+            return new ekb();
+        }
+    }
+    return new EKBOpenSource(); // original EKB
+}
\ No newline at end of file
diff --git a/src/netmd-interface.ts b/src/netmd-interface.ts
index 1767d78..4ca3d86 100644
--- a/src/netmd-interface.ts
+++ b/src/netmd-interface.ts
@@ -22,6 +22,7 @@ import Crypto from '@originjs/crypto-js-wasm';
 import { NetMDNotImplemented, NetMDRejected, Status } from './netmd-shared-objects';
 import { HiMDFactoryInterface, NetMDFactoryInterface, RH1FactoryInterface } from './factory/netmd-factory-interface';
 import { getDescriptiveDeviceCode } from './factory';
+import { getEKBObject } from './netmd-ekb';
 
 enum Action {
     play = 0x75,
@@ -933,35 +934,6 @@ const discforwire: { [k: number]: number } = {
     [Wireformat.lp4]: DiscFormat.lp4,
 };
 
-export class EKBOpenSource {
-    getRootKey() {
-        // prettier-ignore
-        return new Uint8Array([
-            0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xf0,
-            0x0f, 0xed, 0xcb, 0xa9, 0x87, 0x65, 0x43, 0x21
-        ])
-    }
-
-    getEKBID() {
-        return 0x26422642;
-    }
-
-    getEKBDataForLeafId(): [Uint8Array[], number, Uint8Array] {
-        // prettier-ignore
-        return [
-            [
-                new Uint8Array([0x25, 0x45, 0x06, 0x4d, 0xea, 0xca, 0x14, 0xf9, 0x96, 0xbd, 0xc8, 0xa4, 0x06, 0xc2, 0x2b, 0x81]),
-                new Uint8Array([0xfb, 0x60, 0xbd, 0xdd, 0x0d, 0xbc, 0xab, 0x84, 0x8a, 0x00, 0x5e, 0x03, 0x19, 0x4d, 0x3e, 0xda]),
-            ],
-            9,
-            new Uint8Array([
-                0x8f, 0x2b, 0xc3, 0x52, 0xe8, 0x6c, 0x5e, 0xd3, 0x06, 0xdc, 0xae, 0x18,
-                0xd2, 0xf3, 0x8c, 0x7f, 0x89, 0xb5, 0xe1, 0x85, 0x55, 0xa1, 0x05, 0xea
-            ])
-        ];
-    }
-}
-
 export class MDTrack {
     constructor(
         public title: string,
@@ -1117,13 +1089,15 @@ export class MDTrack {
 }
 
 export class MDSession {
-    constructor(private md: NetMDInterface, private ekbobject: EKBOpenSource, private hexSessionKey?: string) {}
+    constructor(private md: NetMDInterface, private hexSessionKey?: string) {}
 
     async init() {
         await this.md.enterSecureSession();
-        await this.md.getLeafID(); // Panasonic compatibility
-        const [chain, depth, sig] = this.ekbobject.getEKBDataForLeafId();
-        await this.md.sendKeyData(JSBI.BigInt(this.ekbobject.getEKBID()), chain, depth, sig);
+        const leafId = await this.md.getLeafID(); // Panasonic compatibility
+        const deviceId = this.md.netMd.getProduct();
+        const ekbobject = await getEKBObject(leafId, deviceId);
+        const [chain, depth, sig] = ekbobject.getEKBDataForLeafId();
+        await this.md.sendKeyData(JSBI.BigInt(ekbobject.getEKBID()), chain, depth, sig);
         let hostnonce = new Uint8Array(
             Array(8)
                 .fill(0)
@@ -1131,7 +1105,7 @@ export class MDSession {
         );
         let devnonce = await this.md.sessionKeyExchange(hostnonce);
         let nonce = concatUint8Arrays(hostnonce, devnonce);
-        this.hexSessionKey = retailmac(this.ekbobject.getRootKey(), nonce);
+        this.hexSessionKey = retailmac(ekbobject.getRootKey(), nonce);
     }
 
     async downloadTrack(trk: MDTrack, progressCallback?: (progress: { writtenBytes: number; totalBytes: number }) => void, discFormat = discforwire[trk.getDataFormat()]) {