Double dipping at CBA

I was having all sorts of problems using Comsec to manage my accounts using my software. I have since joined Etrade, and after having been trading with them for a year, I have not had any significant problem. Etrade has never had to contact me, and I have only had to contact them once to change my address. They did make one stuff up - I asked them to change my address, but instead they set up a new account. But all is forgiven, they dont make a habit out of it.

The law requires CBA to keep its broking activities separate from its banking activities. One day, I had to pay default fees for not having money in my account. As indicated, I have not had this problem with Etrade. I dont know why the problem occurs with Comsec. My possible explanations are:
1. Their software systems dont update all the time so I am misled into thinking there is money in my account when there isnt
2. Their software doesn't account for incomplete trades - so there is a mismatch between the balances that I discover too late
3. They dont provide customers will a real-time statement of their account balance, so customers have to make their own calculations. If you are trading alot this is not easy. Instead I had to calculate how much money is due to settle in 3 days, and how much will be paid within 3 days. Etrade calculates those amounts for me :) I even asked Comsec if they can set my account on the same terms as Etrade, so there is no 3days credit (settlement), but they couldnt. All very silly!

Anyway, to this day I never realised why this occurred. The attitude of the bank however was incredible. As far as they were concerned I was a 'defaulter' and they closed my account. I was overseas at the time, and whilst they say they tried to contact me....I doubt it. They sent a letter to my Australian address but I was not in Australia to receive it. In fact they knew I was overseas, but I actually dont expect them to act on that. My email was my preferred mode of communication - they didnt use it. I dont think they should shut down an account without warning, and I dont think they should undermine a customers ability to trade. I asked them why they didn't just restrict my ability to buy new stock, but maintain my ability to trade out of existing positions. No explanation!
They closed down my account and had my electronic CHESS certificates converted into Holding Statements. The implication is that I could not trade these stock for weeks in a falling market. They probably cost me $10,000. Do you think they took adequate precautions to protect my interests as a customer. Do you sue a bank for $10,000? Of course their contract allows them to do that. But do you expect that type of behaviour. According to the Ombudsman, they have no case to answer. It would require legal action.

They did not offer any warning before closing my account. In fact I had tolerated the account defaults for some time. It was costing me $30 each time. I complained when they charged me $30 twice - once for Comsec, then again for CBA - thats the double dipping part.