cleaning the blow off tube?

I use better bottles and with the limited head space I always need a blow off tube. I clean it by soaking in PBW and hot water overnight. Then I sanitize the tube with star san just prior to hooking it up to the fermenter

BUT the tube always smells like the last beer I made. Should I worry about the tube being a source of contamination? Do you guys replace the blow off tube every so often because they get funky?

Any plastic that you use in brewing will smell like beer over time. I like to replace my buckets and hoses after 10 uses. That's probably a little overkill, but why risk it?