DSL sound cutting out

Tatzmann

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Specially programmed chip and or accompanying diode can cause troubles in
the newer DSLs, namely DSL100H and 40Combo
amps.

There is a thread on here and a couple on
other forums about this.

This might be part of your amps defect, maybe.
 

PelliX

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Specially programmed chip and or accompanying diode can cause troubles in
the newer DSLs, namely DSL100H and 40Combo
amps.

Specially programmed chip? As in, somebody reverse engineered the RL_MUTE operations out of the firmware, or? It should be doable, but desoldering to flash is going to be harder for most than replacing a cap or the diode, indeed.
 

Tatzmann

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Im not into programming, chips and this
type of stuff. I pointed out a known problem
with those amps, he can do further research.

Specially programmed should only mean that
the "firmware" or whatever program is on it
is made specifically for this amp and therefore
not obtainable through something like mouser,
you have to call a Marshall Service center to get this part.

Good for you that you know your way around
this stuff.
 
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PelliX

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Im not into programming, chips and this
type of stuff. I pointed out a known problem
with those amps, he can do further research.

Good for you that you know your way around
this stuff.

I was honestly just curious, as I had indeed considered simply forcing no-ops into the firmware, but never took the time to desolder, dump, poke, flash, resolder, etc. I'd take the easy way, bypass the relay or ensure it had a permanent voltage source if I didn't trust the chip. From what I've seen, most of the time the little ATmega is fine, just resetting itself due to current starvation.

@jacktheexcynic @Rokinroller Read the voltage if you like and report back, then we'll know what's up most likely.
 

Rokinroller

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Yes, most likely. But the relay is probably not at fault, it's the supply from the microcontroller. And the clue is (often, no guarantee) that it's starved of voltage itself. Check the VCC on the IC and the relays when engaged. There's a cap inline with the VCC which may need replacing. If you need exact details search the forum here or I'll dig up the schematic tomorrow.
Super . Thank you so much . Yes I did a good search and found good stuff . Yes seems to be a low voltage to chip . Caps and diodes suspect , not the programmed IC . Great help here !
 

Tatzmann

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In this thread the guy found a permanent solution for the locking of the channels/sound
cutout on a DSL100H. But it was some sort
of workaround because changing of this chip
didnt help permanently.

idk if this helps.:shrug:
 

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