OD-1 has low end floppy compressed sound..advice needed

[rosssurf]

I have built the vero layout of the boss OD-1. The low end gets compressed and floppy when the gain is turned up above 60%. What could be causing this? I have done all of the mods suggested in RED with the exception of placing a 2M2 from input to ground? What is the purpose of this resistor Do I put this across the input jack? or somewhere on the board itself?
Link to the build
http://aronnelson.com/gallery/Martys-layouts-and-photos/OD_1update

[MartyMart]

Did you increase the size of C1 and C2 ?  ... could = "Mud" if you did.
Also try R6 and C3 as "stock" value first ( 4k7 and 0.047uf )
This effects gain/bass roll off as gain is increased  !

Output cap C7 1uf can be made smaller too, perhaps 0.22uf or 0.1uf
would be fine for a thinner tone.

MM.

[rosssurf]

Thanks MM. C1  is stock 0.047uf.   C2 is 0.0056 instead of 0.0047. Could this slight change in C2 make for mudd?? I will try the orriginal value and see.
R6 is 3k3 as per mods and not "stock 4k7.   C3 is "stock" at 0.047.
I will try a 4k7 in place of the 3k3 @R6 and see.

What is the pourpose of the "2M2 resistor to ground". How exactly do I connect it?  Do you know?

I will try lower values in C7 as well.

[MartyMart]

I'm not sure that your one small cap increase will make the pedal "muddy", I would
check out your wire up and make sure you have no errors, my layout does work, but
isn't the "neatest" that I've seen 
The 2m2 would go from board "input" to ground at the front, directly after the jack input
wire.
It's just to stop "popping" when using a DPDT or 3DPDT switch for bypass.
C7 much smaller, will thin it out some, if you think overall it's too "thick" sounding, let me
know how it goes.
Cheers,
MM.

[rosssurf]

I removed C3 and it sounds great! I do not know if this makes sense, but o well!