GGG's Phase 100 question re: depth

[Bucksears]

I built the Phase 100 from GGG's layout, but didn't use a rotary switch. Instead, I used two SPST switches, one for regeneration and one for depth. When the depth switch is open, I pretty much have two options: regeneration open and closed; I get a phasing sound and all is well. With the depth switch closed, there is a VERY faint phasing sound that you can barely hear, and you can only hear THAT with the speed turned up.

Has anyone else had this problem?

- Buck