Although its new season is off to a solid ratings start, viewers may be tiring of Dancing with the Stars.

Monday night's two-hour premiere of the ABC reality dance competition series' ninth season averaged 17.5 million viewers and a 4.1/10 rating/share in the Adults 18-49 demographic while Tuesday night's two-hour broadcast averaged 15.2 million viewers and a 3.5/9 rating/share among Adults 18-49, according to Nielsen Media Research's Primetime Preliminary Fast National Data ratings figures.

While Dancing with the Stars' Monday night broadcast won its time period among total viewers, it finished second among Adults 18-49 behind Fox's broadcast of the two-hour season premiere of House, which averaged a 6.5/16 rating/share among Adults 18-49.  House finished second among total viewers, averaging 14.8 million viewers.

Monday night's ratings numbers were also well below those of last fall's Monday night premiere of Dancing with the Stars' seventh season, which averaged 21.1 million total viewers and a 5.3/13 rating/share among Adults 18-49 during the first night of a similar three-night season debut.

Dancing with the Stars' Tuesday night broadcast finished second among both total viewers and Adults 18-49. 

CBS' broadcast of NCIS' seventh season premiere won the 8-9PM ET/PT hour by averaging 20.0 million viewers and a 4.6/13 rating/share among Adults 18-49 -- both of which were all-time series highs.  The series premiere of the show's new NCIS: Los Angeles spinoff then won the 9-10PM ET/PT hour by averaging 18.3 million viewers and a 4.3/11 rating/share among Adults 18-49.

Tuesday night's ratings numbers were also well below those of Dancing with the Stars' seventh season Tuesday night premiere, which averaged 18.2 million total viewers and a 4.7/12 rating/share in Adults 18-49.