RCCrawler Forums - Steering servo twitchy, RX or TX problem?

heya Crawlers! Long time lurker first time poster here with a problem I need to pick your brains on before i go out and spend more money on new parts.

I just got a used Axial SCx24 and the steering servo "sometimes" twitches over to one side when I turn my TX dial/steering wheel. The steering servo seems to react when I play with the trim and DR settings on the TX.
Here's some things I've troubleshooted

- I plugged the stock steering servo into the CH2 (motor) and it works when i go forward/backward on the TX
- I plugged a brand new HS-55 (low volt servo) into the STR slot on the RX and it reacts the same way as the stock one
- I attempted to rebind the RX and TX and the same issue appears

Do I have an RX or TX or Servo issue here? I don't have an extra TX to bind/test with.
EDIT: Is there a way to know if it's not a TX issue?

Thank you all in advance!