Seeking a second opinion

Hi all,

I would love to hear your opinion and advice about a situation ,  here's the short story :

About a year ago,  someone want me to build an insert switcher for him,  8 balanced stereo insert, 2 ch with m/s,  1 ch with blend knob.

The unit done,  and works good and clean. Actually this is not the first unit I build, I've build few for other studio before and after this one.
The unit full of Burr Brown chip,  INA137 balanced receiver,  DRV134 balanced line driver,  OPA2134.

After a month later he put in on his small  studio setup,  he said that there's weird noise  when the M/S engaged,  the m/s channel was connected to the diy igor sontec eq he bought, unfortunately he cannot do test procedure to see which one cause the problem,  the m/s circuit or the outboard (by jumper the encoder output to decoder input) .

I told the owner to ship back the unit to investigate as unit warranty, but unfortunately he refused and prefer his studio tech guy to look at it.
His tech guy said that it is the power supply capacitor fault that make the DRV134 (m/s output balanced driver) make the noise.

His diagnostic was really surprising and technically non sense to me, because I use DRV134  chip in every circuit in this unit (monitor level circuit,  blend circuit,  output att. buffer). My logical thought was , if it's the PSU issue,  then the noise would be everywhere,  and always there,  because they share the same PSU. I really doubt his diagnosis on this.

Does that make sense to you?


Best,
Simon

Was he able to fix the noise ?

Could be BS could be something else, hard to ever know for sure.  If he replaced a cap, ask for the old one back so you can test it.

JR

Not dealing with the technical side but...

If the unit was in warranty and he chose to have his tech to make a non-authorised repair, I'd say that all bets are off in terms of you taking any responsibility for the unit now.

This is what any manufacturer would do if a non-authorised repair was carried out while still in the warranty period isn't it?

When in doubt do what is right (treat a customer as you would like to be treated. )  8)

That said if you don't know who the sucker is in the poker game "you are the sucker".  : Don't be the sucker.

Good luck.

JR

if it were the psu, i would suspect it everywhere unless you decouple  the Psu.

rob_gould said:

Not dealing with the technical side but...

If the unit was in warranty and he chose to have his tech to make a non-authorised repair, I'd say that all bets are off in terms of you taking any responsibility for the unit now.

This is what any manufacturer would do if a non-authorised repair was carried out while still in the warranty period isn't it?

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yes, that is normal procedure for a manufacture.

no user service able parts inside. warranty void if opened  by non-authorized personal

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JohnRoberts said:

Was he able to fix the noise ?

Could be BS could be something else, hard to ever know for sure.  If he replaced a cap, ask for the old one back so you can test it.

JR

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Despite that other circuit surrounding runs clean?  Same chip same PSU?

I'm not following them anymore, but it doesn't matter he able to fix or not,  because I'm not willing to pay $300 for something that not technically make sense to me.

In this kind of situation,  I told the tech guy to send the unit back to me before he move any further,  but it's look that they choose their own way, I heard that the problem became worst,  and they still blame me on this.

What was the disputed $300 you weren't willing to pay for?
Did you yourself get paid for the project?

Without having the unit, or at the very least the supposed faulty cap, in hand it'd very hard to reach any conclusion regarding component faults or anything. 

Sounds like you build this sort of thing from time to time.  It may be that the only thing you can do is attack the circuit from every angle next time you do build one.  For instance, does PSRR worsen in M&S coding and decoding config.?  I'm not saying it does, just a 'for instance'.  Sounds like you're already satisfied the circuit is robust, but reinforcing your confidence in it is always good. 
Good luck

JohnRoberts said:

When in doubt do what is right (treat a customer as you would like to be treated. )  8)

That said if you don't know who the sucker is in the poker game "you are the sucker".  : Don't be the sucker.

Good luck.

JR

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Well, I should not play poker with him at the first time, especially after what we have hard discussion here https://www.facebook.com/groups/1458538374409630/permalink/1947325872197542/ . I know that he was very upset on how I brake his prejudice opinion, and how  the other member turns out against him.  A month later he  ask me to built  the switcher for him for,  he paid  $1250 for this unit.

I start thinking that he make it personal , and planning something not good,  Incite others,  "negative campaign",  etc.
That's why  I ask for second opinion about what his tech guy diagnosis,  just to make sure that I hold the right card  on this game.
                         

Winston O'Boogie said:

What was the disputed $300 you weren't willing to pay for?
Did you yourself get paid for the project?

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He estimate the cost for his tech guy,  the guy that work for him for long time. it's just before give the unit to his tech guy  and  after he refused to ship back the unit to me  as warranty. He put paypal dispute too, but rejected by paypal. 

I will happy to pay  if it's make sense. Sometimes I reimburse to pay local tech for simple task like replacing faulty switch,  etc, but for something that need further investigation I recommend to ship back .

He  paid $1250 for the unit with spec he want to have. 

rob_gould said:

Not dealing with the technical side but...

If the unit was in warranty and he chose to have his tech to make a non-authorised repair, I'd say that all bets are off in terms of you taking any responsibility for the unit now.

This is what any manufacturer would do if a non-authorised repair was carried out while still in the warranty period isn't it?

Click to expand...

yes,  although it's low price, I give all my works 2 years parts and service warranty,  but sometimes for simple task (replacing faulty switches,  opamps) I send the replacement parts and  pay local tech to handle it,  it's  save time and  the shipping cost.

pucho812 said:

no user service able parts inside. warranty void if opened  by non-authorized personal

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in the name of curiosity, I'm not sure  if that's relevant for such as single custom build product (?)
But  I agree that's not good idea

Sounds to me like he is trying to scam you.

Cheers

Ian

ruffrecords said:

Sounds to me like he is trying to scam you.

Cheers

Ian

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I believe it's not about money,  but something else.

I don't see how he can expect you to pay a repair that you did not ask for?

You asked for it shipped back, he wouldn´t do that, your responsibility pretty much ends right there.

And as you cannot know what potential damage has been done during unauthorized local repair, the warranty is off.

Jakob E.

simonsez said:

My logical thought was , if it's the PSU issue,  then the noise would be everywhere,  and always there,  because they share the same PSU. I really doubt his diagnosis on this.

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Don't neglect the possibility that when replacing the "faulty" cap, the tech may have displaced something, like the sitting of an IC in its socket or of a wire in a connector.

simonsez said:

He estimate the cost for his tech guy,  the guy that work for him for long time. it's just before give the unit to his tech guy  and  after he refused to ship back the unit to me  as warranty. He put paypal dispute too, but rejected by paypal. 

I will happy to pay  if it's make sense. Sometimes I reimburse to pay local tech for simple task like replacing faulty switch,  etc, but for something that need further investigation I recommend to ship back .

He  paid $1250 for the unit with spec he want to have.

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Presumably your written warranty does not authorize him contracting a repair and then billing you.

Sounds a little fishy to me...

JR

PS: I have seen obscure faults before so try not to be too absolute about what other people experience. 

The experienced "weird noise" with m/s switch on was noticed with a signal on input or just eq and switcher connected without any sound going through?
Note sure what to think when noise in not really defined, I mean if it's distorded signal, hiss, buzz, or high pitched sound...

+1 failure to follow warranty path voids claim. 

Warranty is clearly gone.

Still you could play nice and offer him something. Then it's up to him to accept or reject.

You could contact him by saying that you DO understand that he's disappointed and that YOU have an interest after all in him being satisfied with his purchase.

So you could kindly ask him to describe the INITIAL (!) problem more in detail and then have him send the unit (trackable) back to you for inspection. But also explain that, as for costs, shipping must be paid by him now, cos you had offered repair under warranty, which he -- stupidly, I'd say -- ignored.

As for costs of fixing,  I'd say, it depends on you. If you can do it within one hour, you could not be bothered. Don't forget to test the unit extensively afterwards though and document the results just in case. Then send it back to him (and maybe post about it on FB).

If it would take you longer to fix the unit, cos his tech did all sorts of things, send him a quote for repair OR offer to buy the unit back from him (kind of like partial reimbursement) for what you think it is still worth after alteration (parts etc or minus hours of work needed).

If he doesn't agree to either of the two, tell him that you will send the unit back to him at your cost, and then do it, and then forget about it.  Make sure all steps are (photo-) documented and/or public (on FB).

Of course your customer will 'lose' money this way, but he should have followed the warranty procedure in the first place -- and he needs to know that.

Whatever his motives, in the above way he should end up with a working unit and be happy. You also said you suspect it's not about money ? If not that and if not disappointment, what then ?? Or is it something you couldn'thave done  much about in the first place ?

Anyway, question is: Do you think it's worth all the hassle?
He shouldn't have voided your warranty !

gyraf said:

I don't see how he can expect you to pay a repair that you did not ask for?

You asked for it shipped back, he wouldn´t do that, your responsibility pretty much ends right there.

And as you cannot know what potential damage has been done during unauthorized local repair, the warranty is off.

Jakob E.

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Actually,  I give him a chance to check the unit after he insist to fix it with his tech guy,  may be it's just loose connector or something,  but the diagnosis mail report was make me drop the agreement,  because it's non senses to me and  ridiculous. 

Instead of fixing the problem (if they exist),  the tech guy keep talking/ criticizing how I built the unit, keep telling me how I should did here and there.  It make me suspicious about their motivation,  I suspect he ordered by someone to did that (negative review) . I will happy to pay technician to fix the problem,  not to make irrelevant negative  review summary,  especially in this kind of situation,  trust is very important.

I smell bad intention here. Funny thing,  that the tech guy start posting the unit pic on his facebook lately,  I 'm not sure that's ethical thing for a professional technician,  and I very surprise how easy peoples come into prejudice opinion.

Sorry my bad english  :-[