• BeatMaker 2.2 users - route events to MidiBridge's own virtual output to be picked up in BeatMaker and not the 'BeatMaker 2' destination. Have flagged this with Intua.
• BeatMaker 2.2 and SynthStation 25 users - use FreEWI to remap the range of the SS25 keyboard down two octaves to control the drum pads.
• Animoog (for iPhone) users - there is an issue with Animoog terminating the network midi session when it is started. To workaround, select 'MidiBridge' in Animoog's MIDI input option and then return to MidiBridge and re-make the wifi connection.
• Music Studio users - currently Music Studio cannot co-exist with some other audio apps running in the background. Audio from these apps is muted when Music Studio runs. The most notable is SampleTank.
• Music Studio users - Tip: to generate track MIDI events (eg. for MidiBridge to pass to another device via wi-fi), the MIDI Output mode must be set to 'Tracks'.
• SynthStation 25 and Midi Mobilizer (original) users - please make sure you're running iOS5 or events from these devices will stop when MidiBridge is backgrounded.
• SynthStation25 and Midi Mobilizer (original) users - there is a bug in MidiBridge when you mix these with CoreMIDI inputs in some cases. Fix has been made and will appear in next release.
• We have found a bug where in some cases with multiple physical interfaces, MidiBridge sends the events to the wrong output. This has been fixed and will be included in the next release. In the meantime there is a workaround: just set an empty filter on each of the input ports that are in use. This will make the events take a slightly different path through the code and route to the correct output. Fixed in version 1.1
• System exclusive messages larger than 1010 bytes can't be sent over the CoreMIDI network interface. This seems to be a problem with the iOS driver from Apple. Note, this does not affect external interfaces.
• System exclusive messages larger than 255 bytes can't be received via the CoreMIDI network interface. This seems to be a problem with the iOS driver from Apple. Note, this does not affect external interfaces.

• Turn off the Visual Events option in MidiBridge. In slower systems this is important.
• Terminate as many apps as possible so they are not running in the background taking CPU cycles unnecessarily.
• Set up a filter on the incoming interface to filter out as much unwanted data as possible. Blocking 'TimeSong' for instance will filter out ticks and active sense messages which may not be needed depending upon what you're doing.
• Run a little bit of MIDI data through beforehand (maybe to a channel with no sound?) to get iOS to page MidiBridge into memory.

Events stop working after about 5 seconds after I background MidiBridge
If you want events to be processed while MidiBridge is in the background you need to ensure that the 'Run in Background' option on the MidiBridge Preferences pane is switched to 'On'. By default, this setting is 'Off' as running in the background can cause extra battery drain and we want our users to consciously switch on the option and be aware of that. Even when backgrounded, MidiBridge (and MidiVision) will suspend itself after 20 minutes of no events being received to conserve the battery (a local notification is issued by MidiBridge to inform you this has happened). Also, you must be running iOS5 if you are want to use MidiBridge in the background with the original Midi Mobilizer or SynthStation 25.

I want to connect MIDI inputs to an app that supports CoreMIDI network (but not virtual MIDI)
It's a sneaky trick, but you can tell MidiBridge to connect to itself in the Settings pane and the CoreMIDI network interface becomes (very close to in terms of speed/latency) a virtual MIDI input. Step by step:

• First, make sure CoreMIDI network input on MidiBridge is *not* connected to anything. We don't want infinite loops or duplicate events!
• On the settings page, enter the word 'localhost' in the hostname and press the 'Connect' button.
• Back on the interfaces page, connect the inputs you want passed to the other app to CoreMIDI Network out.
• In the other app, tell it to listen to CoreMIDI Network.

Can I connect two iOS devices together without a router?
Not currently. iOS will not create ad-hoc wi-fi sessions and the personal hotspot feature will only route to the internet and not to the local device. Maybe this will change in the future, but for now, a router/access point is needed to interconnect two iOS devices. You don't need a router/AP if you want to connect an iOS device to a computer, since the computer can create the ad-hoc session and the iOS device can connect to it.

How fast does the app turnaround an event?
During development we attempted to measure the turnaround times of events especially in busy stream situations. We ran a busy MIDI track of 12,827 events over a 4 minute and 51 second period and measured the time taken from receiving the message to having finished dealing with it, all within the app.

Newer devices with faster processors naturally enough process the messages quicker than older devices, but even with an old iPod Touch 2G and original Midi Mobilizer the app was able to pass the events with an average delay of just under 2 milliseconds:

If any MidiBridge user would like to see these metrics on their own system, drop us a line and we'll tell you how to get them.

• ESI MIDIMATE II - unable to use midi thru with this device due to an incompatibility issue with how this interface works. No workaround - fix in next release. Fixed in version 1.3
• New bug in V1.2 where settings migration code causes the app to crash. Please delete the app and download again as a workaround. Fixed in version 1.3
• Channel aftertouch messages can cause problems and stop events from being seen by MidiVision. This issue will soon be fixed in a Line6 firmware update. 4 Feb 2011 - Resolved in MidiVision V1.1
• Some real-time messages (time clock) are currently not available to apps via Line6's SDK. This issue is also being addressed by Line6 in a pending firmware update. 4 Feb 2011 - Resolved in MidiVision V1.1

How much data can be handled?
Again, this depends. MidiVision has a feature where it monitors the data throughput and if it reaches a certain threshold, it will temporarily disable the screen event updates in order to process the data as a priority. You'll see the 'spinning wait indicator' when this happens. Once the data throughput drops, MidiVision will catch up and display the captured data. Of course, the system as a whole (iDevice/iOS/Midi Mobilizer/SDK/App) can only handle a finite amount of data in a given time period. What this actually is will depend upon the speed of the device's chip, other running apps and amount of memory. Your mileage may vary, as they say.

• Silent4 1.4 occasionally incorrectly determines silent/ringer mode. Fixed in V1.5 currently at Apple for review.
• iOS5 - Silent4 does currently not work as the mechanism used to determine the state of the silent/ringer switch no longer works. Currently looking for an alternative method. Fixed in version 1.4
• The 'sent at' time shown on the reminder messages is sometimes incorrect. This happens when the day of the month is one digit, so happens between the 1st and 9th of each month. A fix has been identified and will be included in the next release. Fixed in version 1.3
• Occasionally the app issues a termination message when the app still appears to be in memory. In iOS 4.2 and above this problem appears to be significantly reduced

Could you not change the app's icon when silent mode is detected?
Unfortunately this is an Apple limitation. It is not possible for a third party app to alter its icon during run-time.

I can't enter a time less than 5 minutes
Since the app gets triggered every 10 minutes, entering a value lower than this does not make sense. Therefore the app will force the time to be 5 minutes if you try to set a lower value.

Why does it take a few minutes before the badge changes?
The public iOS function that Silent4 uses only permits an application to wake up at 10 minute or greater intervals, so generally it can take up to 10 minutes before Silent4 notices a change in the silent/ringer switch. However, this interval is decreased if you are moving, as the app is woken up by the location monitoring system in iOS. You can always bring the Silent4 app to the foreground to force it to update immediately, although generally the 10 minute interval works pretty well given that usually people don't switch their phones in and out of silent mode every minute.

The badge isn't changing and I'm not getting reminders - I use a bluetooth headset
The way Silent4 detects silent mode is through a side effect in the audio system of iOS. If a bluetooth headset is connected (or headphones or other audio accessory), Silent4 cannot determine the state of the switch. If Silent4 is in the foreground, it will warn you of this. If it is in the background, it assumes the silent/ringer switch is in the same state as it was before the audio accessory was connected. Unfortunately this is a limitation of the app. We're hoping that Apple will one day add a more reliable mechanism to determine silent/ringer state.

Why do I sometimes get a message that Silent4 has been terminated?
Periodically when memory runs low, iOS does some housekeeping where it 'jettisons' apps to make room for others. Sometimes Silent4 can be one of the unlucky ones. To combat this, if Silent4 is terminated you will receive a local notification after about 30 minutes after termination. You can touch on 'View' to restart Silent4, or if you don't want your silent switch monitored, you can just touch 'Ignore' and you will need to remember to start Silent4 yourself again if you want to use it.

Could you not issue an audible alarm when on silent like the iPhone's clock does?
There is a way of doing this (and remaining within Apple's API rules), but this requires playing audio all the time in the background which is a battery drain. Also, this method is unreliable and the alarms will not trigger after an incoming phone call or if the app is restarted. Unless Apple were to provide a different method of sounding an alarm (low probability) providing audible reminder alarms is not a feasible option.

How do I stop Silent4 from using location services completely?
As of version 1.3, unchecking the 'Location Reminders' tickbox will immediately disable GPS usage. There is no need to disable the app's access to location services via the Settings app anymore.

The iPhone's Low Power GPS mode really is very efficient. Essentially it uses cell tower triangulation to determine a less accurate position. If you have your cell radio on (and who doesn't on their phone?) then using low power GPS mode adds very little usage of the battery. Tests on an iPhone 3GS show that over a 24 hour period the battery is drained by about 10% only and most of that is just keeping the phone running. If you believe that Silent4 is depleting your battery, it might be worth checking what other apps are still running.

When I touch the icon, the application seems to crash.
You probably have the 'Quit Immediately' setting turned on and the 'Quit Delay' set to 0 seconds. This is normal behaviour and is the fastest way to set the reminder. You can always revert back to the default settings in the iPhone's settings panel.

I'm not getting any push reminders!
There could be a number of reasons for this:

• Your settings do not permit push messages. Verify the following in your iPhone's Settings panel. Notifications is 'On' and in the 'Silent' section of Notifications that Sounds and Alerts are both on.
• The Silent application does not have 'Push Reminders' set to 'On'. Go into the iPhone's Settings panel, and scroll to the 'Silent' section. Make sure 'Push Reminders' is set to 'On' and that the other parameters (hours/minutes to wait) are set to something that suits you.
• You ran the app (with the above settings correct) and with the silent switch slid to the downward position. This schedules the message. If you switched the silent switch back up and ran the Silent app again, this will cancel the push message.
• You are running the 'Basic' version beyond the trial period. Push reminders are no longer available when the Basic trial has expired. You will receive a dialog when the trial period has elapsed.

This app doesn't work on iPod touch
That is correct. The iPod Touch has no silent mode.

Why does the app tell me to unplug headphones?
The app detects the silent switch setting using the audio toolbox. If headphones are attached it cannot determine correctly whether the iPhone is in silent mode or not. Just unplug the headphones, press the app's OK button in the dialog and plug the headphones straight back in.