The 3Trax system seemed to fix the problem on mine.
For SiriusXM, I used a "pluggable" radio. If you think about it, it makes much more sense than a permanent radio.
https://www.amazon.com/gp/product/B00I59XQKO
Why?
Because I have docks in most of my vehicles. I have one in my Jeep Wrangler, one in my Jeep Cherokee, one in my motor home, and one in my truck. Experience has told me I can't drive more than one vehicle at a time. So, I can unplug it from my truck and put it in the RV when we go on a trip. Then when we arrive, I can unplug it from the RV and put it in the Jeep we towed. One subscription, saves ~$100 a month per vehicle. I also have a boombox I can plug it into for use at our pool, or by the RV for those rare times we want music while camping.
https://www.amazon.com/SiriusXM-SXSD.../dp/B00M0FDN9I
In the 33SW, I never found a good place for the antenna. I simply placed the antenna on top of the car mount that came with the radio. I'm sure there's a better way though.
EDIT: Forgot, the CO2/Propane sensor went out on mine, too. I unhooked it, took out the factory smoke detector and put in a Nest Protect. This way I get alerted on my phone if something goes wrong. I kept thinking "what if the RV catches fire outside the house while we are asleep?" Problem solved.
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