diff --git a/rpcs3/Emu/Cell/PPUDisAsm.cpp b/rpcs3/Emu/Cell/PPUDisAsm.cpp
index f84097b03f..20e40cbef8 100644
--- a/rpcs3/Emu/Cell/PPUDisAsm.cpp
+++ b/rpcs3/Emu/Cell/PPUDisAsm.cpp
@@ -2318,5 +2318,5 @@ void PPUDisAsm::UNK(ppu_opcode_t op)
 		}
 	}
 
-	Write(fmt::format("Unknown/Illegal opcode! (0x%08x)", op.opcode));
+	Write("?? ??");
 }
diff --git a/rpcs3/Emu/Cell/SPUDisAsm.h b/rpcs3/Emu/Cell/SPUDisAsm.h
index b640bc6042..27d4394cd0 100644
--- a/rpcs3/Emu/Cell/SPUDisAsm.h
+++ b/rpcs3/Emu/Cell/SPUDisAsm.h
@@ -966,8 +966,8 @@ public:
 		DisAsm("fms", spu_reg_name[op.rt4], spu_reg_name[op.ra], spu_reg_name[op.rb], spu_reg_name[op.rc]);
 	}
 
-	void UNK(spu_opcode_t op)
+	void UNK(spu_opcode_t /*op*/)
 	{
-		Write(fmt::format("Unknown/Illegal opcode! (0x%08x)", op.opcode));
+		Write("?? ??");
 	}
 };