Digitech RP-55 added to my Pedalboard but with noise problem

[Platefire]

  I've got a switchable looper pedal on my pedalboard with two loops. with loop #1 I run all my analog pedals through and haven't been using loop #2. So I got the idea of getting a small pedal size digital effects processor to use in loop #2 to bring in special effects when I want something a little bit different. So I picked up this RP-55 at a pawn shop for $27 in like new condition. Kinda impressive all the effects that the little cheap pedal produces. I've been tweaking the settings to make usable patches to use with my existing line up of songs. Intent was to just dial up the patch on the processor and click the loop in and out when I need it in conjunction with my other analog pedal loop.
  This is working well but when I use my favorite analog Route 66 Overdrive I'm getting a hum related to power supply that's bugging me. Can't hear it while playing but when the music stops it's annoying.
Even when the #2 loop with the RP-55 is switched off it still causes hum with the Route 66 distortion/or compressor turned on. The only way to stop it is disconnect the power supply to the RP-55 and then it stops when the Exf pedal goes dead. Do I need to buy a seperate Digitech RP-55 power supply to stop the noise?? or what is the solution. This is a rather old 90's SKB PS-25 Pedalboard that uses a class 2 500 ma power supply. The RP-55 requires 300 Ma so that leaves 200Ma for the Route 66, Dunlop Tremolo, Boss Super Chorus and Boss Tuner. I'm thinking I might need a 1000 Ma power supply now? Am I stretching my existing power supply to far and that's causing the hum? Platefire  
  

[Cups]

They're not getting along. Could be a current issue. I'd buy a seperate adapter. Dumb things are overly expensive though arent' they?

[Platefire]

Problem Solved! First I tried a 1200 mA Koss Class 2 power supply(PS) I had on hand to power the whole pedalboard and same problem no different! So next I tried a Danelectro 200 mA PS I had recently bought to quiet down my Fab Delay pedal. So I just hooked the danelectro PS direct to the RP-55. That did it! These older PS just will not work on these newer pedals. Platefire

[Platefire]

I've had this idea for a while to put a small pedal sized processor on my pedalboard for varity. Wow! I guess I'm analog spoiled because I can't hardly take digital distortion anymore. It's all so sterile and raspy sounding. I'll leave it on there for now. Guess it was a nice thought that didn't prove out. I've been mostly using just the reverbs. Platefire