Wow that is terrible is it just this model or are all new ONKYO using this limiting feature?
The protective nanny mode was triggered during a continuous 5W@8ohm test on ASR...
Are they being overly protective? possibly...
In the real world, no one on the various Forum threads has encountered this issue with their 4ohm speakers!
I did encounter some issues with my 4ohm (nominal, spec) speakers, but they have a minimum impedance of 1.6ohm.... yet even with that, my Integra DRX3.4 (which uses the same amp design, and has the same nanny protection circuit ) never went into "protection"
But consider:
1) 5W continuous would be way way too loud in my setup and room (typically my amps run at around 1W, with occasional rare moments of up to 4W, and momentary peaks that have never exceeded 16W)
2) There were clearly issues driving my speakers... imaging was poor, vocals/dialogue was confused - moving to an external amp resolved these issues immediately! - hence my assumption that it was unhappy with the low impedance.
3) I also tried it with my 8ohm alternate speakers (B&O Penta) and it handled them just fine!
4) Many people with 4ohm speakers participate in the forums and have never experienced the nanny mode protection circuit... so real life looks different from that specific lab test.
I think the whole "nanny mode" protection circuit thing, is a storm in a teacup, and should be ignored.