The big new investment advice is … boring?

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The long bull market has spawned a lot of advice about the next big play, but analysts are now changing gears to tell investors boring is hot.

"This is not the time to be taking a big swing at the market. This is the time to be slipping quietly into the background," said Benjamin Pedley, head of investment strategy for Asia at HSBC Private Bank. "Sometimes when we come to do these roadshows and we're sort of upbeat and [say] 'this looks interesting,' what we're sort of saying now is just be a bit boring."

He expects increased volatility ahead, especially heading into a potential U.S. Federal Reserve move to increase interest rates this year, and noted that "crowded" trades such as the U.S. dollar and high-yield bonds could unwind aggressively. HSBC's private bank is advising clients to go neutral on equities, with an increased allocation to cash, and Pedley said he's focusing more on defensive plays, such as going overweight on Singapore stocks to capture a combination of defensiveness and high dividend yields.

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Others have a slightly different take on how to play boring. Bank of America-Merrill Lynch is advising heading toward index components.

"The key mandate for consultants in selecting funds is to avoid paying active fees for benchmark hugging," analysts there said in a note last month. "Funds with high active share are considered to be more attractive. But by virtue of the calculation, maintaining high active share inadvertently forces portfolio managers into smaller names."

That's pushed mid-caps to trade near all-time premia to larger stocks, it said.

"The trade: buy mega cap big old ugly stocks – inexpensive, hard to own, and more out of favor than ever," it said.

Some are positioning in expectation that the equity markets themselves will offer more boring returns ahead.

So far this year, the S&P 500 index's returns haven't even come close to the 19 percent annualized pace averaged over the past three years, noted last week. The index is up around 2.4 percent year-to-date.

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"With nominal gross domestic product (GDP) growth of 4-4.5 percent per year, you can't honestly expect much more than that from equity markets," DBS said in a note "Your favorite stock picker may claim otherwise but he probably won't be your favorite stock picker two years from now."

Outside the U.S., DBS isn't expecting quantitative easing will necessarily drive high returns.

"The 1 percent growth expected in Europe and probably won't support 19 percent equity market returns for three years like the U.S. enjoyed," it said.

Expectations for more boring returns are echoed over at Goldman Sachs.

"Valuations should compress a little bit in the U.S. and stay pretty stable in the other markets. With U.S. earnings already at a record high, we expect only around a 2 percent total return for the S&P 500 over the next 12 months," Peter Oppenheimer, chief global equity strategist at , said in a note last week.

He expects stronger profit growth in Europe and Japan, "but even so, returns are still expected to be lower than those achieved over the last five years given the expected lack of multiple expansion."

—By CNBC.Com's Leslie Shaffer; Follow her on Twitter