In Evans v. Williams & Fudge, Inc., 2012 WL 3025164 (S.D.Cal. 2012), Judge Miller found Rosenthal Act claims subject to arbitration, explaining:

Here, the court concludes that the debt collection practices at issue directly arise or relate to the Promissory Note. As the broad language in the arbitration provision provides that any claim or dispute arising or related to the Promissory Note is subject to arbitration, the court concludes, absent a valid defense, that the arbitration provision is enforceable. Furthermore, any doubt concerning the scope of arbitrable issues is resolved in favor of arbitration. Chron Corp. v. Ortho Diagnostic Systems, Inc., 207 F.3d 1126, 1131 (9th Cir.2000). ¶ The court rejects the defenses to arbitration raised by Plaintiff. First, Plaintiff argues that claims arising under the Rosenthal Act are not subject to arbitration. The court rejects this claim as such statutory claims may be arbitrated.  Armendariz v. Foundation Health Psychcare Servs., Ind, 24 Cal.4th 83, 899, 99 Cal.Rptr.2d 745, 6 P.3d 669 (2000); AT & T Mobility LLC v. Concepcion, ––– U.S. ––––, ––––, 131 S.Ct. 1740, 1748, 179 L.Ed.2d 742 (2001). Second, contrary to Plaintiff’s argument, the language “relating to any claim or dispute arising out of the Promissory Note” is broad enough to encompass collection efforts related to the Promissory Note. Finally, the court rejects Plaintiff’s argument that the arbitration provision is unconscionable under state law. Under California state law the court may invalidate an unconscionable contract provision. Civil Code section 1670.5, subdivision (a) states: “If the court as a matter of law finds the contract or any clause of the contract to be unconscionable at the time it was made, the court may refuse to enforce the contract, or it may enforce the remainder of the contract without the unconscionable clause, or it may so limit the application of any unconscionable clause as to avoid any unconscionable result.”