Onkyo Integra M-588

It sure looks like a sweet piece to own

https://audio-database.com/ONKYO/amp/integram-588-e.html

I have had several Onkyo pieces, liked them all.

hifiengine vinylengine have manuals available

https://www.hifiengine.com/manual_library/onkyo/m-588f.shtml

free membership, then free downloads, limited to a few per day

this may take you to the service manual I downloaded

file:///C:/Users/elliott/Desktop/hfe_onkyo_m-588f_service_en.pdf

perhaps you can find a similar model with meters with explanation of the meters

page 3 ...

The meters switch "automatically" back and forth depending on how many watts are being registered/used (1X for higher wattage and 0.1X for lower wattage).

DeKay

Thank you both, this is really helpful. Appreciate it.

Sorry, I reversed the 1.0/.1 duties, but assume you got the drift.

DeKay (always putting his T-Shirt on backwards).

Got it 😉- thanks again for your help, dekay - really appreciate it

I have 2x M504's that run a little bit warm and they've been fine for years. Just curious, what did you pay for that? They're hard to find and worth quite a bit

Ok. That’s re-assuring. I’ll probably take it for a cleaning at my local dealer. 
I paid approx USD1,600 (purchased it in Singapore). No scratches or anything. Only what I guess is common: the vinyl wood needing a bit of glue.