Huzzah and 3.3v Trinket Noise

[AxisRobotics]

Hi guys, I'm having weird issues with a trinket being in .5" proximity with a Huzzah. Essentially, the trinket is running the Adafruit IR receiver code, then sending it's hex value to the huzzah via RS232, which in turn publishes it via MQTT. I prototyped it on the bread board and both the Huzzah and Trinket were about 4" apart. Once I mounted them to a perfboard where they are only .5" apart, the trinket thinks its getting all kinds of IR data transmitted to it, but its all noise. I've tried various decoupling caps on power rails as well as a pullup on the IR sensor, but still lots of noise. Any ideas?

Update: there is only one wire from the Huzzah to the trinket and that is the RS232 transmit line. Also, when I put the Huzzah in boot loader mode, the noise stops. That is what makes me think the RF signal is causing issues. Help!

Update #2: Found the issue - crazy amount of noise on the 3v line coming out of the Trinket for some reason. Added a .1uF cap between 3v and Gnd right near the TSOP38238 and it solved the problem!

Thanks!
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