USB devices are plug and play (PnP) devices and should just work without issues.
Unfortunately this isn't always the case. We observed issues on busy USB hubs where USB data packets get regularly dropped or the device USB pipe stalls. As a result the Magic Trackpad disables multi-touch mode.
With version 3.1.2.8 we resolved the multi-touch issue, however the USB bus might still has stability issues beyond our control.
Consider to solve these issues to prevent worst case scenarios like data loss on attached hard drives.
Reasons
As the Magic Trackpad Utilities driver is technically only a filter driver (which doesn't handle any bus related handshakes) we can only speculate why these USB issues happen:
- Firmware of the USB hub and/or the attached devices are not fully compatible.
- Connected USB devices support different USB specifications (USB, USB 2, USB 3 Gen…) and interfere at some point.
- Doggy cables and connectors.
Most likely it's a combination of some or all of the above.
Observations
So far we observed USB connection issues:
- Temporary when another USB device gets connected or disconnected (plugged or unplugged).
- Constantly (but not always) when a network adapter is attached, for example a 1 GBit LAN/USB adapter or a USB WiFi dongle.
- Sometimes when a wireless USB Logitech Bolt keyboard dongle is attached.
- Sometimes when more than two Magic Trackpads are connected.
The Magic Trackpad will continue to work but the mouse pointer or scrolling might just hang for a second or two which can be quite annoying when it happens every 10 seconds or twice a minute.
Solutions
Quick fixes (usually doesn't last long)
- Turn your Magic Trackpad off and back on again.
- Unplug the USB hub from the computer and plug it in again.
- Restart the device driver.
- Restart your computer.
Change the USB bus
Usually an internal USB controller has up to 4 USB sockets connected on its bus. For example a computer (or USB hub) with 7 sockets usually has two internal USB controllers / buses.
- Try to separate the Magic Trackpad USB connection from other busy USB devices on a different USB controller / bus. Try different USB sockets on your computer or USB hub.
- If there aren't enough USB sockets (some laptop have only two these days), use USB hubs to separate your devices on different controllers / busses.
- Unplug any USB device you don't really need.
Use a Bluetooth connection
While Bluetooth connections might have their own issues, they can be a stable connection alternative for your Magic Trackpad.
- Unplug the USB cable from your Magic Trackpad.
- Pair your Magic Trackpad as Bluetooth device, instructions are here.