I have bought the same brand model RA-PSCM15. Even though you have the instruction I found that abit confusing, so I directly called to the customer services centre, and they were helpful, you can try to call them and they will answer your questions.
Customer service hotline:
Kwai chung 2406-5439
Causeway Bay 2526-8873
Yau Ma Tei 2332-5961