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Prx 818XLF - Safety/Limp Mode? - Issue Powering On/Off Consistantly


I'm currently sitting in my van at a small festival event that i am caterting sound for.
Music starts tomorrow.

I have x2 818xlf active subs and x2 635 active tops - powered by a 25 kilowatt generator - surge protected power bar.

All speakers were running great all day during setup. Low volume. With a couple of sound checks at higher volume.

I was sitting having a sandwich and one of the subs just turned off. No loud pop, No strange noise other than the usual signal cut. All other speakers still working fine.

The blue light on the front and power light on the rear, Was now in a constant cycle of On/Off for about one second each and continues until you either switch it off at the power button or remove the power cord.

I switched out two new power cords. Same issue.

I switched out the power bar. Same issue.

I switched out the power source and plugged into a socket powering the other speakers. Same issue.

I turned off all other speakers and tried powering on the faulty speaker (in case it was overloading the generator - despite being over kill) - Same Issue.

I removed the back plate to check wire connnections. All look attached. No burnt smells.

The fuse seems to be fine. But i havent switched it. As dont have a spare. I havent taken out the other Sub just incase I break something and then have no subs for tomorrows event. As much as i know about blown fuses, surely it would not power on at all if that was the issue.

This particular sub is only 1 week old.

A friend of mine who has 8 of these subs and more of older models. Has never had this issue with any of his inn years of use and outdoor events.

He suggested it could be an amplifier issue?

Worst case i will run one sub tomorrow and have a little less boom, but any help appreciated.

Thanks Kieron.



  • Hey @Kieron011 ,
    Going through the exact same thing right now - did you ever solve this?

    Thanks! Danny
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