Hi Raman,
found the problem.
The problem is with using paplay. If you set emacspeak-play-args to nil as suggested in the docs, start-process throws a wrong type argument - seems it expects all program args to be stringp. If you set emacspeak-play-args to an empty string i.e. "", then that works, but paplay throws a too many arguments error.
My fix was very basic - test emacspeak-play-args and if it is not nil, call as normal. If it is nil, call without referencing emacpeak-play-args.
I also found a minor issue with the defcustom for emacspeak-play-args. Because it is defined as having to be a string, you cannot actually set it to nil using the custom interface. I have fixed this by changing the definition for the defcustom to use a 'choice options, with one choice being string and the other const.
I've committed my changes to my fork of the emacspeak repo on github. You should be able to do a pull merge. I also added a pull request to the issues, but I don't think your using that, but thought it might send you an email.
Tim
If you have questions about this archive or had problems using it,
please contact us.