@flamini yes it is possible. Using speakers with incorrect impedance or running it at excessive volume can trigger the protection circuit. When it goes into protect mode the amp will shut down with the standby light blinking. You did not tell us if you got out of the protect mode or if you need help with that.
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=== Update (02/17/2018) ===
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@flamini try this:
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* Unplug the receiver's power cord from the wall and leave unplugged for at least one hour. Remove all speaker and audio cables from the back of the receiver while waiting.
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* Reconnect the power cord after at least one hour has passed. Leave the speaker and audio cables disconnected.
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* Turn the receiver on and turn the volume to the maximum setting. Leave the receiver on for 30 seconds. If the receiver shuts off and goes back into protect mode you will need to contact your Onkyo dealer.
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* Turn the volume back to the minimum setting and turn off the receiver.
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* Unplug the power cord from the wall and then reconnect the speaker and audio cables.
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* Plug the power cord back in and then power then turn on the receiver.
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from [https://www.techwalla.com/articles/how-to-reset-onkyo-protect-mode|here]
@flamini yes it is possible. Using speakers with incorrect impedance or running it at excessive volume can trigger the protection circuit. When it goes into protect mode the amp will shut down with the standby light blinking. You did not tell us if you got out of the protect mode or if you need help with that.