Aquaboy, very dark repeats/capacitors

[Ed22]

Hello all,

Just finished my aquaboy board (MN3005)... (had to leave effects alone for a while)
It works... but repeat are really really dark. Also when i hit E high string, there is just one repeat or so... low E string is OK, plenty of repeats.
I've socketed C13, C23 and C27. I'm surprised that there are very few changes when I put 150pF or 100nF in these places. Got some more high but absolutly not a big deal.
So what are these capacitors that are responsible of this filter that cuts all high frequencies?

I've already made a baja wet cat project and didn't get the right sound too. No luck with analog delays.
I own an AD80 and an AD900. Repeats are not that dark. AD900 is really sweet. Wanted to build aquaboy to add modulation board. (don't want to mod these two beauties)

any kind of help would be cool,

thx,

Ed.