A potentially bitter public stoush is about to erupt between consumer advocates and industry groups over mortgage broker commissions.In a submission to the government this week, CHOICE is expected to call for a blanket ban on all trail and bonus commissions to address concerns raised by the Australian Securities and Investments Commission that these payments create conflicts of interest for brokers.While industry groups such as the Mortgage and Finance Association of Australia are already conceding some ground on volume-based bonuses, CHOICE faces resistance from brokers on its trail commission proposal.The public debate is shaping as a modified re-run of the tortuous Future of Financial Advice (FOFA) battle, which after many years of wrangling resulted in the abolition of volume-based payments in the financial planning industry.Canberra politics will largely determine the complexion of whatever legislation is brought before federal parliament, with cross-bench senators, particularly from the Nick Xenophon Team, likely to exercise influence over any legislated outcomes.Senator Xenophon was a key driver among independent senators who overturned the Abbott Government's FOFA reform package in 2014.History might repeat itself on the sensitive issue of trail commissions.MFAA chief Mike Felton has urged his 13000 members to "voluntarily" engage in the reform process, but comments made by some brokers on industry chat rooms suggest that the industry body itself faces a backlash if the changes lead to unwieldy regulation.Comments posted by subscribers to the broking industry website, The Adviser, seem to indicate that brokers have little appetite for changing the commission structure.While Felton told The Adviser earlier this month that avoiding the issues raised by ASIC was "not an option", subscribers to the site accused his organisation of acting as a mouthpiece of the Australian Bankers Association.That criticism is likely misplaced, but it gives an insight into the way brokers are thinking at the moment.One of their big fears about the reform push is that the banks will try to exploit it so they will eventually hand over less cash for every mortgage origination.The MFAA agrees with ASIC that volume-based bonuses paid by lenders directly to brokers should be banned."The MFAA proposes the immediate removal of volume-based payments made from lenders directly to brokers," it stated in the submission to Treasury.Notwithstanding, the MFAA argues that bonuses should still be paid -  but only via the aggregators - and that they should be calculated on broader performance criteria, not just the value of mortgage business written. That concession plays into further tricky terrain for the MFAA because one of the biggest complaints of brokers across the industry is the time it takes their aggregators to distribute payments coming from lenders.ASIC's reform program is unearthing more than the inevitable tensions between consumer advocates and financial services providers.It's also exposing an arrhythmia of self-interest across the whole mortgage supply chain.