I decided to upgrade my SN3 power amp for a NAP 250 DR which was discounted due to being both OC and cement coloured. Now I have just received it and there is an oil (I think) leak coming out from the bottom of the 250 DR. Any idea what this is and whether I should even plug it in or send straight back. Pictures below and ideas gratefully received.
Looks like the cooling oil has leaked from the transformers. 
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Have you checked the serial number to verify that it at least seems possibly a genuine Naim product?
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Certainly will be genuine. No-one trying to counterfeit would ever choose concrete over black!
In any case it needs to go back to the dealer asap.
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I’m unaware of toroidal transformers such as used in this having oil cooling - but I admit to not being familiar with Naim’s transformers.
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It’s the area under where the transistors and cooling blocks are bolted down into the chassis. Exposed to serious sun light and heat? I have no idea what the melting point is for the paste between transistors and heat sink but that’s the only thing I can think of if it’s not a blown capacitor leaking.
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Yes it is genuine or a really elaborate fraud involving someone impersonating a Naim dealers website, answering the telephone and speaking German and knowing about Naim products and offering counterfeit versions of a poorly received product 
Appreciate this is always possible but I think we can rule it out.
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Believe there can be something used between Power Transistors and their Heat Sinks…?
Think it can be Silicone based - so Silicone oil or grease…?
Google says -
What is heat sink compound? Heat sink compound (also called thermal grease, thermal compound, CPU grease, heat paste, heat sink paste, and thermal interface material) is a sticky paste that’s used as an interface between CPU heat sinks and heat sources .
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The leak may just be where there is a route out. Doesn’t mean that’s where the oil is coming from (if it is oil). Maybe it’s a leaking electrolytic.
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But it’s white not brown.
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The location of the leak suggests its heatsink related… 
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As I mentioned before, where it’s coming out doesn’t necessarily mean anything except that is where the hole is!
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It may be from the thermal grease - there has to be some between the chassis tray and the cover as the latter acts as a heatsink. Otherwise, one for @NeilS I think…
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IB, I think Skeptical said this rather tongue in cheek.
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Thanks Richard - it certainly could be grease. Question is what to do ? I will wait for @NeilS before doing anything as I don’t want to turn it on before being told it is ok to do so. I will also send the dealer the pictures and let him know that I might well send it back. Of course the problem is that there is only a refund available as the dealer has no more cement coloured 250’s and I really want a new one to avoid recapping as long as possible. But damaged goods need to go back in any case.
I will also say the concrete is no where near as bad as people suggest. I rather like it if truth be told.
This is just thermal grease … nothing to worry about if you ask me.
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Naim’s transformers are not oil cooled… 
I am very sure of this.
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