You can try a flexible hose inserted into duct and connected to a shop vac. Use a low to medium power shop vac so as to not damage the duct. You should be able to hear a change in the vac speed when you capture the mouse.
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2015 Freedom Express 248RBS
TV 2015 Silverado HD2500 Duramax
TST Tire Monitors
Honda 2000I + Companion
2 100W solar panels
Moved to the General TT/5th Wheel Discussion section.
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Dan-Retired California Firefighter/EMT
Shawn-Musician/Entrepreneur/Wine Expert
and Zoe the Wonder Dog(R.I.P.)
2016 PrimeTime TracerAIR 255, pushing a 2014 Ford F150 SCREW XTR 4x4 3.5 Ecoboost w/Max Tow Package
4pt Equal-i-zer WDH and 1828lbs of payload capacity