Hello,

I have had some recent issues with one of the two DigiMax FS units with loss of phantom power to four of the inputs.

I had an acquaintance come by to help me to determine what the possible cause was and he made mention of the following article.

Attachment 2717

Source: Patchbays

Also, the following are his comments, "But most of all, I know from my embarrassing experiences taking a synthesizer mic preamp to Backline and being asked if I used the phantom power through a TRS
patchbay or the time I built custom gear for someone heading out on tour and plugging in their TRS footswitch immediately blew the supply because I didn't put rectifier diodes to protect from the reverse voltage (short). Remember, using TRS - XLR cables is fine. It's just having phantom power on while patching the TRS creates the issue."

As to my current concern, I use an internal mic'ing system that uses phantom power via a TRS endpin jack which then goes to a male XLR plug for connection to the interface.

As to my question then: "Would inserting a TRS plug into a TRS endpin jack while connected to a socket with phantom power enabled, cause such a short?"

Anyone care to comment on this?