HELP! PIO LX60 can't set 6Ω speaker?

gxxrge

Wasted my half day till can't set up 6Ω speaker, i can't find 6/8 Ω according to the manual p.73:

Switching the speaker impedance:
We recommend using speakers of 8 Ω with this system,
but it is possible to switch the impedance setting if you
plan to use speakers with a 6 Ω impedance rating.
1.  With the receiver in standby, press STANDBY/
ON while holding down the SETUP button.

2. Select SPEAKER using ↑/↓, then select 8 Ω or 6 Ω
using   ← /  →.
• SPEAKER 6 Ω – Use this setting if your speakers are
rated at 6 Ω.
• SPEAKER 8 Ω – Use this setting if your speakers are
rated at 8 Ω or more.

Any HELP?