Portable DAC electrical noise

Hello,
I own a fiio q1mk2 and just bought a balanced cable for my DM6.
But now I have the problem that I get extrem electrical noises from my phone when stuck to the Q1MK2.
It even happens when the Q1MK2 sits next to the phone.
This only happens or is only hearable through the balanced out.
Can someone give me advice how to fix this or isolate the phone from the dac?
Are there other portable dac Amps which have proper shielding?

Copper foil tape can help prevent electrical noise.

Did you ever figure this out? I’ve used several portable DAC/amp and I don’t believe I’ve experienced this problem at all. I suspect if you get any other DAC, it would fix the issue.

Have you connected the Q1 II with USB OTG cable to your source as DAC/Amp or wirh the 3.5mm to 3.5mm cable as AMP only?
I have a Q1 II as Backup lying around and have had similar problems with the 3.5mm connection before my Fiio Android otg cable arrived. But did not have any problems with balanced IEMs or Headphones with the OTG cable using it as DAC/AMP with my phone or Tablet.

Depends on the phone and amp combination. Try a longer cable and keep the amp away from the phone. If the noise goes away then it’s radio interefence. Only thing you can do is separate them. I have the same problem with my Little Bear amp. I use a longer cable and keep the LB in my pocket.