I'm similar in that I'm a one-man-band and do mostly business work and occasionally top it up with residential work.
I've only been a member of BNI for about 5 months but I had very few small jobs. Perhaps if your chapter is pushing everyone hard to give referrals that's where the weak referrals given are coming from. I'd encourage you to really look closely at the message you're putting across though. Some of the things I recommend:
* Have a tagline and make sure it says business. (I'm not very creative so for me it's simply "IT Zen - For Small Business IT"). Say that tagline every time you speak.
* Focus your weekly message on business problems/solutions: SharePoint, QuickBooks upgrades, server upgrades etc
* Talk a LOT about your ethics, your communication, and how you like to go above-and-beyond to delight your customers. Give examples to prove it. Why? If someone refers a friend to you to get Windows upgraded there's not a lot that can go wrong. For someone to refer a business client of their own to use your services though then that can potentially go very badly for the referrer. They need to know that you will do a great job, because your work is a reflection on them. I did my ten minute talk last week and I pretty much said that word for word. Show that you understand this and will treat referred customers right.
* Don't talk much about what you do at a technical level. No-one else cares, and if you talk too much techno-babble it will reinforce the idea that you are a geek, and not someone that understands business.
* Adjust your message slightly every week, but always frame it in business terms. Ie. If you talk about the Cryptolocker virus one week, do NOT talk about how you can repair the virus. Instead talk about how it can encrypt shares on servers and the importance of backup and disaster recovery.
* Don't be afraid to stand up and say "The key for success in my business is picking up businesses in the [x] to [y] employee size". Be explicit about what you want. If you still have crappy referals coming through say "I'm finding I'm too busy to focusing on my customers these days so am no longer taking on residential work". (This may not be completely true, but it should stop the unwanted referals).
* Also, be specific about the referals you want each week. Rather than saying "This week I'm looking for referals for law firms", instead say "I think I can provide a lot of value to Smith & Jones Law Firm. If anyone knows any decision makers at this company I'd love an introduction". Chances are someone knows someone at that company, and by being specific you are far more likely to get a 'hit'.
* Treat everyone in your BNI chapter like they're an existing client of yours, and you want to have a conversation with them about some aspect of their business IT. Show that you understand and can solve business problems that they may be having. So rather than saying "This week I'm after a referral for a company that needs their backups audited", get up and say "How many people in this room know if their server backups succeeded last night? Shouldn't you know? For those of you with working backups, how many of you know how long it will take to recover everything in a disaster scenario? If your server died at 4pm, how much data would you lose? What is the cost to your business to get it back? Can you even get it all back?". Then offer to perform a free audit of backup systems for all BNI members. Showing that you can proactively solve their business problems also shows them that you understand and can solve their customers problems too.
* Speak to each relevant member (ie. web designer, insurance guy, accountant, business consultant, electrician) and say you'd like to catch up with them one-on-one. Meet over a coffee and learn more about their business and listen out for items you can help with. If the electricians do IP camera installs chances are they could use someone to help them figure out "all that IP stuff". Perhaps the business consultant has a standard CRM system he recommends but it doesn't talk to Xero. Maybe you can help automate it. Talk to the insurance guy about backups, disaster recovery and business continuity. Show that you're an expert in the area and you have solutions, including cheap or free ones. You may be surprised at how many problems you can solve come out of these conversations, and you've now planted the seed in these members minds.
My mindset with BNI is not to make millions from direct referals. My focus is on trying to meet people at other companies, do small jobs for them and do those jobs very well (and at a fair price). So for example when I speak to the electrician about helping set up the networking side of the IP cameras they put in, my interest isn't in that work. My interest is getting on-site to all of their clients and meeting them. If possible I'll try to talk about other IT stuff while I'm there. If an employee swears at their computer I might offer to help. Or I might notice that their USB backup drive is dusty (ie. hasn't ever been taken off-site) so I can offer to purchase and set up a second drive so they can have off-site backup. I couldn't care less if I make $0 on the IP work and on the backup job. The key thing is I have met another business and shown that I can solve IT problems, that I can communicate clearly, that I'm good value for money and I'm proactive If that company isn't happy with the value or quality of service they're receiving from their current IT provider I want to be top of their mind.