Mortgage rates saw little change this week as investors await news from the Federal Open Markets Committee (FOMC) about a possible third round of quantitative easing.

According to Freddie Mac’s Primary Mortgage Market Survey, the 30-year fixed-rate mortgage (FRM) averaged 3.55 percent (0.6 point) for the week ending September 13, no different from the week before and only slightly above its all-time low achieved earlier in the summer.

The 15-year FRM averaged 2.85 percent (0.6 point), slightly down from 2.86 percent in the previous survey.

The 30-year fixed average has stayed below 4.00 percent all but once this year, while the 15-year fixed average has been below 3.00 percent since the last week of May, Freddie Mac reported.

The 1-year adjustable-rate mortgage (ARM) also stayed the same this week, averaging 2.61 percent (0.4 point). The 5-year ARM average slid down to 2.72 percent (0.6) from 2.75 percent a week ago.

The results of Bankrate.com’s weekly survey were a bit more mixed. The 30-year fixed averaged 3.81 percent, inching up from 3.79 percent previously. The average 15-year FRM did not change.

At the same time, the 5/1 ARM slid back, averaging 2.75 percent (from 2.76 percent the week before).

“Mortgage rates were little changed over the week as a better than expected report on the services sector offset a lousy employment report,” Bankrate.com said in a release. “But the weak jobs picture did increase the likelihood of further Fed stimulus, such as purchases of mortage-backed bonds that would drive mortgage rates down further.”

Fed chairman Ben Bernanke is expected to hold a press conference Thursday afternoon to announce the outcome of FOMC’s policy meeting.