The S&P/ASX 200 Index (ASX: XJO) is having another difficult session. At the time of writing, the benchmark index is down 1.6% to 7,765.3 points.

Four ASX shares that are falling more than most today are listed below. Here's why they are dropping:

Breville Group Ltd (ASX: BRG)

The Breville share price is down 2.5% to $31.45. The catalyst for this has been the appliance manufacturer's shares going ex-dividend this morning for its interim dividend. Last month, Breville released its half year results and reported a 10.1% increase in revenue to $997.5 million and a 16.1% jump in net profit after tax to $97.5 million. This allowed the Breville board to increase its fully franked interim dividend by 12.5% to 18 cents per share. Eligible shareholders can now look forward to being paid this dividend later this month on 28 March.

Flight Centre Travel Group Ltd (ASX: FLT)

The Flight Centre share price is down 4% to $13.70. As well as being caught up in the market selloff, some industry news could be weighing on the travel agent giant's shares. Earlier this week, Delta Air Lines (NYSE: DAL) downgraded its guidance due to weaker than expected demand. And with the US potentially heading for a recession, investors appear concerned that this could have a big impact on the travel market as a whole.

Orica Ltd (ASX: ORI)

The Orica share price is down over 2% to $16.53. Not even the announcement of a new on-market share buyback has been able to stop this commercial explosives company's shares from falling with the market today. Orica has announced a $400 million buyback, which will commence on 28 March and run for 12 months. Orica CEO, Sanjeev Gandhi, said: "The on-market share buy-back is aligned with our refreshed capital management framework to be announced today and demonstrates the Board and Management's confidence in Orica's financial strength and outlook now and into the future."

ResMed Inc (ASX: RMD)

The ResMed share price is down 6% to $35.31. This has been driven by news that some insiders have been selling the sleep disorder treatment company's shares. This includes ResMed's chief commercial officer, Kaushik Ghoshal, selling US$2.3 million worth of shares. Goldman Sachs is likely to see this as a buying opportunity. Earlier this week, the broker put a conviction buy rating on the company's shares with a $49.00 price target. This implies potential upside of almost 40% for investors over the next 12 months.