Looking at the schematic shows that pin 7 of IC5 is disconnected, with both inputs grounded. It will not make a difference. So the circuit should be OK.
Can you also measure the transistor pins?
Something I just realized is: You are powering it at 10v. BBDs are very sensitive to bias. When I say very sensitive, I mean less than 1V can make a huge difference.
First: The Bias of the BBD is still at 4.8V (pin 3 IC2) and the output is at 4.2v (pins 7 and 
. What does the document say about using other voltages? There is at least one change that is necessary (R13). I only ever seen this pedal powered with 9v or 12v, never 10v. You may have to change R13 to something between.
Second: The bias of 4.8v is probably for 9.4v (as stated in the document). That means: 10.3/9.4*4.8 = 5.3v. I would start there. If you cannot get there, try reducing 82k. Some people even suggest that it is not necessary and may only reduce the ability to change the bias.
Do you have an oscilloscope?
If you do not have one, turn the bias trimmer until there is no flanging on one side, and then turn it the other way around until there is no flanging. Mark this two points, there is a high chance that the ideal bias is exactly in the middle. You can then fine tune with your ears.
Flanging is more pronounced with the feedback on max., but then you cannot hear the original repeat clearly. Try with the feedback at min. too.
Trimmer T1 also changes the feedback. See how it sound when it is at the lowest setting. You don't want the loud oscillations now.
Is the filter matrix position working? I think it is easier to test everything with the LFO setting, and with the rate pot at half way, where the flanging occurs slowly.
The clock trimmer should be adjusted so that you have a weird chorus like sound at half of the way and a normal sound on the other. In one direction it will go deeper into chorus territory and have lots of hiss, too much to the other side and you end up not having the flanging, because the clock is too fast and you are into that territory where it sounds kind of dry.
I think in filter matrix mode there is no LFO, so you are at a fixed clock setting. Try measuring pin 3 of IC4 or pin 7 of IC6.
By the way, do not use the voltages in the document as a reference for setting the trimmers (you can multiply them by the same factor 10.3/9.4 I used, to see how they should look like)
Last but not least, BBDs can be noisy. Hiss is normal at some settings.
PS: I was writing this, when I saw your update. I think the noise is incorrect bias+wrong adjustment of the trimmers and not a bad transistor or leaking cap.
Hey Thomasha,
I can take transistor voltages and report back when I get home this evening.
Regarding my 10v of power, I'm really not sure why that's happening seeing as how I'm using a 9v power supply (a standard boss style power supply and then a 9v port of a truetone one spot power supply with the same result).
I forgot to mention earlier in the thread that I took madbean's note about R10 and replaced 82k with a 1k. I've since removed and soldered a jumper, however it made no discernable difference.
The issue doesn't seem to be improper biasing (at least not only that) as there is no setting with the trimmers that results in no noise. If the effect is engaged there is noise/hiss/wooshing/distortion no matter where the trims are set or the combinations of the trims. The noise intensifies when the bias trim is set in what would likely be the "right" spot, but there is always noise.
I think zerro's mention of the low pass filter needing some attention is a good road to go down next. However, as I'm new to reading schematics, I'm not entirely sure where to find the low pass filter or which particular components are making it up. Any help with that would be greatly appreciated. I hate that I need someone to walk me through that at such a granular level, but that's the way it's got to be right now haha. I also have some new transistors and a couple new 3007s on the way to try out just in case. Thanks again! Sorry it took me so long to reply.
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