Just tracked down this Logic 7 glitch, which is not a bug, but an undocumented issue. When a Pluggo has a parameter (pp) defined with “choices”, the value range MUST match or Logic won’t validate the plug-in. By this I mean, if you have 3 choices listed, your value range must be from 0 to 2, NOT 0 to 3.

Note that this is counter to the example given in the MSP Reference Manual, p326.

This seems to be a strict adherence on Logic’s part to the AU spec. Yes, Apple’s auval tool (see below) catches the error, but Apple’s live testing application, AU Lab, did not catch it, and ran fine. Reports also said Digital Performer loaded and ran my plug-in without error as an AU.

The good news is, it’s easily fixable once you know the problem!

Cheers,
Leigh

PS: It’s easy to check your with the auval command line tool (installed by Apple’s Core Audio SDK). Here’s the relevant excerpt from auval’s output, for my plug-in that was failing validation:

Parameter ID:7
Name: Range
Parameter Type: Indexed
Values: Minimum = 0.000000, Default = 0.000000, Maximum = 3.000000
Flags: Readable, Writable
Parameter has Value Strings
Num Strings = 3
ERROR: Unequal number of strings for parameter value range
Value: 0, String: Classic
Value: 1, String: Guitar
Value: 2, String: Bass
-parameter FAIL