For the last two days, every trade for SPZ2 and NDZ2 at CME has been in an exact multiple of 111 contracts, and the total volume is always a multiple of 1100. It also happens on the browser version of TWS.
What cache? If you mean the browser cache, I don't think that "regular" TWS uses it. The problem happens on both versions. Already tried rebooting. btw, I know of at least one other person who's seeing the same thing.
Sorry, I don't know what you mean. If IB has multiple servers which service TWS, I'm not aware of any way the user can determine which server is handling the current TCP session. The best I could do from my side would be to determine the IP address and port.