Ross r-80 delay signal loss- Help!

[Stompin Tom]

My ross stereo analog delay suffers from terrible signal loss.  That is, when the effect is on, the orginal signal (not the delayed) is quieter and has much less low end.  This even occurs when I turn the mix all the way down (eliminating all the delayed signal).  I can get around this by sending the 'remote' output to a second amp, but I'd rather not haul around two amps... 

So, onto my questions: Does anyone else have this pedal and have this problem?  Does anyone have any ideas on how to fix this (is there some reason for the bass rolloff?)?

I've found an old string with a link to the schematic on someone's website (in the schematics section):

http://www.geocities.com/diygescorp/

I'm new to this site.  It's been great so far.  Hope someone can help!  Thanks.

[Stompin Tom]

I've been thinking about this.  Let me ask a specific question.  If I were to change the value of the input(?) cap (say the .01u or the 510p to ground at the beginning of the circuit on the schematic), would that potentially solve the low end roll off problem?  I assume I'd want to lower the value.  If this were a cheaper pedal, I'd just start experimenting, but I don't want to screw any of those old SAD chips up.  Any ideas (or warnings?)...  thanks.