When you are asking me a question about something, and you have a definite idea of how you expect me to answer, ask me a specific question that will elicit the answer you want. Don't ask "how well does it perform?" when what you want to know is "how many packets per second can it push?" or "how many videos can it play at once?".
If you can't work out how to phrase the question in a way that makes the type of answer you want obvious, be prepared to have to go back and forth; I'm a software engineer, not a telepath. When I respond to your question with a question of my own, it's because I'm not clear on what you want to know; I'm not trying to shove you away.
Don't get upset when I answer a question with an apparently evasive answer like "well, it's like this if you're thinking of UK Freeview, but like this if you're thinking of New Zealand Freeview, and like this if you're thinking of US cable". I'm not aiming to be deliberately irritating - I want to give you the most accurate answer I can, so that you can avoid accidentally misleading people.
I will lapse into jargon - if you understand it, it's clear as day. If you don't, say so, tell me which bits of jargon are confusing you, and I will try and explain it better. Again, I'm not trying to confuse, I'm trying to help.
When you ask me a question, give me context; don't just ask the question you think you want answered, but include details of why you want it answered. Sometimes, I'll come up with a solution that doesn't need an answer to the question you thought of; sometimes I'll find a way to give you an answer that isn't what you wanted, but that solves your problem perfectly.
Make it clear when you want a detailed answer, and when you want a high level overview; "Can we do this?" is likely to get a "Yes, but there are these problems you need to be aware of when you try and do it" or a "No, but if we did this instead, you'd get a similar result" - I expect you to know enough about why you want to do this to know if my caveats or suggestions are helpful. "I'm filling in a checklist for a bid - can I tick this box?" will get you a "Yes", a "yes, but you have to understand it this way", a "no, but if you pretended they meant this instead you could", or a plain, "no, you can't".
Finally, remember that I'm a person, too, and that means I want to help you if I can - don't cut me off or get annoyed when I offer an answer that isn't what you want; instead, work with me to get yourself an answer that's possible, and that you can live with.