AT 5555N weird mic wiring issue

Some of you may have seen in "information and guides" how I got the channel buttons on my Adonis M308 working with this radio.    The channel down button bridges the channel select common to the TX wire via a 2200 ohm resistor, and channel up does the same thing with an 11 ohm resistor.   When I wired up the Adonis mic, I nicked the resistors from the stock mic and wired them into the mic connector.  Channel select works just great on the Adonis.

I photographed the resistors so that I could order some for the stock mic and replace them.   Got a new 2200 ohm wired in and channel down works.   However any 11 ohm resistor I try just seems to create a dead short, ie. when you press ch. up, it acts as a TX key, rather than changing the channel.   The original is definitely an 11 ohm, I checked it with a multi meter as well as checking the stripes on a resistor calculator tool online.   The new resistor colours match up.   They are rated for 1/4 of a watt, which surely is fine for a simple push button circuit.    The 2200 is only that I think.

It's not a big issue for me really as I don't plan to use the stock mic but it's something which is bugging me and teasing my curiosity.  It would be good to find out what the issue is in case I want to wire up any other mics with channel buttons.   Does anyone have any idea what is so special about the 11 ohm resistor which I took out of the stock mike?

They could be 11uH chokes...