radio cuts out at higher volume

[NewmbaTX]

just the stock deck in a 06 mobius... with stock speakers (6)..

no amp.

Well, the problem is what David here explained...He beat me to it!

You can rewire the cabins or don't play so loud...or get an amp. The rewiring of the cabins will work, but will reduce power output to the rear speakers = less volume/ sound, but will remain stable.

[Txskyski]

I'm having the same problem in my '07 Outback. It came with the factory amp/sub/tower speakers and it never cut out until I added an extra amp and sub. Now it is doing what everyone describes - it cuts out at louder volumes. The stereo shuts off and re-starts. Does anyone know how to fix this? Is it common that adding an additional amp would cause this?

Thanks

[DOCDRS]

I'm thinking I was experiencing this on my 09 w 6 cabins a subwoofer and 4 tower speakers and 2 amps till I added my ws 420. does that sound right ?

[EarmarkMarine]

Txskyski,
Invest in a $10 to $20 multimeter. You can't do any meaningful diagnosis without first verifying that your voltage is good. And check it at the terminals of the component that is shutting down while its under load. Typically shutdown is due to thermal, protection from an inordinately low impedance, DC flow between components or low voltage. A multimeter will measure continuity, resistance and voltage...all essential in diagnosing a problem.
Disconnect the additions a see if it works okay again. This would be an indication of the problem.
If the amplifier is grounding via the source unit RCA link or the inverse, this could cause a shutdown as the current is increased. Just because it initially works at lower volumes doesn't mean you have a good ground or supply. All grounds and supplies need to reference the same point or battery. Every individual component needs a healthy ground. Re-check all connections and terminations.
Water damage can cause corrosion or a collection of mineral residue on the traces. Things may still function at low current draw but a higher draw will expose the problem.
That's a start and should encompass the most likely culprits. Usually diagnosis is a simple matter of step by step isolation and elimination.
Check back in and let us know what you found.

David
Earmark Marine