Error on power off: uncaught exception: Cannot read property 'removeAllListeners' of null

[JayVee2]

V2.1.5.: When an existing RM4 Mini is powered off, then there is an uncaught exception error.
This behaviour is reproducible.
Not severe but disturbing in log, see below.

-jayvee

`

Quelle	Zeit	debug	Meldung
host.PI3	2020-10-18 00:24:27.377	info	instance system.adapter.broadlink2.0 started with pid 30877
host.PI3	2020-10-18 00:23:57.313	info	Restart adapter system.adapter.broadlink2.0 because enabled
host.PI3	2020-10-18 00:23:57.296	info	instance system.adapter.broadlink2.0 terminated with code 0 (NO_ERROR)
broadlink2.0	2020-10-18 00:23:56.725	warn	} with reason TypeError: Cannot read property 'send' of null at Broadlink.discover (/opt/iobroker/node_modules/iobroker.broadlink2/broadlink_fj.js:2102:24) at async Timeout.doPoll [as _onTimeout] (/op
broadlink2.0	2020-10-18 00:23:56.725	warn	(24054) Promise problem unhandledRejection of Promise Promise { TypeError: Cannot read property 'send' of null at Broadlink.discover (/opt/iobroker/node_modules/iobroker.broadlink2/broadli
broadlink2.0	2020-10-18 00:23:56.720	error	at async Timeout.doPoll [as _onTimeout] (/opt/iobroker/node_modules/iobroker.broadlink2/broadlink2.js:419:21)
broadlink2.0	2020-10-18 00:23:56.720	error	at Broadlink.discover (/opt/iobroker/node_modules/iobroker.broadlink2/broadlink_fj.js:2102:24)
broadlink2.0	2020-10-18 00:23:56.720	error	(24054) TypeError: Cannot read property 'send' of null
broadlink2.0	2020-10-18 00:23:56.719	error	(24054) unhandled promise rejection: Cannot read property 'send' of null
Unhandled	2020-10-18 00:23:56.717	error	promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch().
broadlink2.0	2020-10-18 00:23:56.705	error	at processTimers (internal/timers.js:497:7)
broadlink2.0	2020-10-18 00:23:56.705	error	at listOnTimeout (internal/timers.js:554:17)
broadlink2.0	2020-10-18 00:23:56.705	error	at Timeout._onTimeout (/opt/iobroker/node_modules/iobroker.broadlink2/broadlink_fj.js:469:11)
broadlink2.0	2020-10-18 00:23:56.705	error	at reject (/opt/iobroker/node_modules/iobroker.broadlink2/broadlink_fj.js:403:18)
broadlink2.0	2020-10-18 00:23:56.705	error	(24054) TypeError: Cannot read property 'removeAllListeners' of null
broadlink2.0	2020-10-18 00:23:56.702	error	(24054) uncaught exception: Cannot read property 'removeAllListeners' of null

`