TORONTO -- Traders using at least two major online discount brokerage platforms are complaining of sporadic outages and expressing frustration that the latest glitch has tied their hands amidst a broad plunge in marijuana stocks.

Clients of TD Bank's WebBroker and Royal Bank's RBC Direct Investing platforms have again taken to social media to gripe about problems, after facing similar issues in recent days.

A TD spokesman says "unprecedented" trading volume continues to drive some intermittent delays for its online and mobile WebBroker clients, and the bank's technical teams are continuing to work to resolve the issue.

Brandon Colwell, an economics student and WebBroker user, says he has lost at least $8,000 today and the outages on Dec. 29 and on Jan. 2 appear to be coinciding with surges in trading activity in the cannabis sector.

Several marijuana companies took a major hit today -- with shares of Canada's biggest licensed producer Canopy Growth (TSX:WEED) down as much as 19 per cent -- after the Associated Press reported U.S. attorney general Jeff Sessions planned to rescind an Obama-era policy that allowed legalized pot to flourish in states south of the border.

At least four cannabis-related firms listed on the Canadian Securities Exchange were temporarily halted today, according to the Investment Industry Regulatory Organization of Canada, due to the single-stock circuit breaker rule which limits sudden price swings of stocks.