Troubleshooting
Ads Not Showing
Step-by-step troubleshooting for empty ad slots — check the console for [advlume] errors, verify the script is loading, confirm site approval status, disable ad blockers, and match slot keys exactly.
Low Fill Rate
Why ad slots are empty more than expected — missing ads.txt, low consent rates, Tier-3 geo traffic, narrow ad sizes, high price floors, and IVT-suppressed demand partners.
Low CPMs
Low CPMs are often structural (geo, content category, seasonality) rather than a technical issue. This guide separates expected CPM variation from actionable configuration problems like ads.txt gaps or poor viewability.
Video Ads Not Playing
Checklist for outstream (format attribute, hb-video.js loading, rmp-vast CDN, autoplay policy) and instream (vastReady event, VAST URL validation, content requirement) video ad issues.
Layout Shift (CLS) Issues
Prevent Core Web Vitals CLS from ad slots by pre-reserving height with min-height CSS — recommended values per format, responsive media query variants, and how to collapse empty slots without causing a shift.
ads.txt Errors in GAM
How to resolve the three common GAM ads.txt warnings — missing file, missing seller entries, and invalid format — and how long it takes GAM to re-check after you fix the file.
Console Errors & Debugging
How to read the [advlume] console log — every key lifecycle message explained, the network request checklist, how to enable verbose debug mode, and browser extension conflicts to watch for.